摘要:

LIX.-The h‘ynthesis of Heterogeneous Jf ixed Alkyldiazoanzido-conz-pomds. Preliminary Notice. By RAPHAEL MELDOLA F.R.S. IN a paper recently published by the author and F. W. Streatfeild (this vol. p. 412) it was stated that evidenoe had been obtained that, the mixed diazoamides of the general form X*N,H.Y had double thtb molecular weight usually assigned to these compounds. The com-plete justification of this statement will necessitate a lengthy investi-gation and as the work cannot be resumed for some time to come I propose to give a brief preliminary a.ccount of the experimental results thus far obtained. Expressing these results in general terms, it has been found that two isomeric alkyldiazoamides of the forms X*N,.NR’*Y and Y*N,*NR’*X when boiled together in alcoholic solu-tion in equimolecular proportions combine with the formatiou of B product which is identical with that obtained by first preparing the mixed diazoltmide X*N,H.P and then alkylating the latter.From this it follows that the mixed diazoamides and their alkyl-derivatives are formed by the coalescence of two single molecules and their f o r m u h are accordingly-X*N-N-NH.Y X*N-N-NR’*Y * I I I I Y.N-N-NH*X Y.N-N-NR’*X ’ It appears from this that the compounds produced by the action of diazotised amines on alkylamines contain the grouping -N=N-NR’-. Since the alkyl-derivatives of the normal compounds can also be formed in the same way i.e. by the action of X-N,*Cl on X*NH*R’ it follows that the normal compounds also consist of single molecules. The triple isomerism shown to exist in the paper above referred to may therefore be explained by the formule-I.11. 111. * These formulse indicate the existence of “ position ” isomerides dependent on relative position in the ring of nitrogen-atoms. Evidence has already been obtaintd that such ibomerides are present in the mixed diazo-amidea and their alkyl-deri) a-tives and will be submitted in a later commuricatiou HETEROGENEOUS MIXED ALKRTLDIAZOhMIDO-COMPOUNDS. 61 I The diazoamides themselves are accordingly referable to the types-X*T-$T-NH*Y X*NB-NH*X and Y-N-N-NH~X' Normal. Mixed. Since the compounds X*N2.NR'*Y and Y.N2*NR'*X combine by simply boiling their solutions together whilst X*N,*NR'*X and Y.N,.NR *Y cannot be combined it seemed a legitimate inference that the grouping -NZN-NH- or -NZN-NR'- is stable when the attached radicles are similar and unstable when they are dissimilar and it appeared highly probable that any pair of alkyl-diazoamides might be combined in a similar manner to the isomeric pairs above formulated.This inference has been completely verified by some preliminary experiments and the field has thus been opened for the synthesis of what I propose to call heterogeneous mixed diazo-amides containing totally different aromatic and fatty radicles. The general formula of such cornpounds would be-A*lf-lf-NR'*B X*N-N-NR'*Y ' As a type of this class of diazoamides the following oompound has lieen prepared :-Diazotised metanitraniline combined with methyl-paratolaidine gives the compound On boiling equimolecular proportions of this and the compound pro-duced by the action of diazotised parabromaniline on methylpara-bromauiline a product is obtained which when pure melt's at about 81-82".The formula of this heterogeneous diszoamide is-(m) N 0,. CtjH4*T;I-N-N ( C H3) * CtjH4. C H3 ( p ) (p)Br*c6H4*N-h-N( CH3)*C6H,*CH3( p)' The details of the synthesis will be given in a subsequent commu-nication. The compound behaves in every respect like an ordinary mixed diazoamide being decomposed by cold hydrochloric acid into the usual mixture of diazo-chlorides and alkylamines-+ 2HC1 ( I~L)NO,*C~H~*$T-~;T-N (CH,) .C,H,*CH,( p ) ( p)Br*C6H4*N-N-N(CH3) *C6H4*CH3( p) = (m)NO2*C6H**N2*Cl + ( p)Br*C6H4*N,.C1 + 2( p)C7H7-NH.CH3. This synthesis and others of a similar character which I have recently effected leave no doubt that the mixed diazoamides hav 618 RUHEMANN AND BLXCKMAN BESZOPHENYLHTDRAZISE, double the molecular weight usually assigned to them and the isomerism of the alkyl-derivatives made known in former papers as well its the other properties of these compounds is thus for the first time rendered intelligible. Fitasbury Technical College, July 1889

ISSN:0368-1645    

DOI:10.1039/CT8895500610

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

618 RUHEMANN AND BLXCKMAN BESZOPHENYLHTDRAZISE, LX.- Benzophemy 1 hy draaine. By S. RUHEMANN Ph.D. KA, and F. F. BLACKMAN B.Sc. IN a recent number of this Journal (this vol. p. 242) one of ns pulslished a n investigation on the action of chloroform and alcoholic potash on some hydrnzines and showed horn compounds were formed which contain a closed ring of four nitrogen and two carbon-atoms. I n turn that investigation led to the experiments the results of which form the subject of the present cominunication. Doebner (Annulen 210 267) acted on plithalanil with bensoyl chloride in the presence of zinc chloride and obtained phthalyl-benzoanilide C,Kj.CO.C,H,*~<,,>C,H, co which by alooholic pot-ash is transformed into amidobenzophenone or benzoaniline, C,Hj*CO.CsH,*NH,.This base was regarded by i t s discoverer as a para-amidobenzophenone since he was able to transform it- into paroxybenzoic acid by converting i t into oxybenzopheiioiie and then fusing the latter with potash Froehlich ( B e y . 17 2673) how-ever showed that a benzophenone- derivative could be obtained from pseudocumidine by a metliod perfectly analogous to Doebaer’s. But since the constitution of 9-cumidine i s expressed by the formula C,H,.CH,*CH,.CH,.NH, the bemoyl-group cannot here enter into the para-position this led him to consider the possibility of benzoaniline being an ortho-compound. I n support of this view he adduces the fact that by the action of melted potash molecular t’ransforniations take place; and i t may be that salicylic acid is the first product of the fusion of the oxybenzophenone t’rorn benzoaniline and that paroxybenzoic acid results from its subsequent transformation.But the experiments of R. Geigy and W. Koenigs (Ber. 18 2700) have siiice proved that Doebner’s view of the constitution of benzo-1 3 4 RUHEMANN AND BLACKNAN BENZOPHESTLHYDRAZINE. 61 3 aniline is correct arid that this base is in reality para-amidobenzo-phenone. We have prepared this compound according to Doebner’s method, in order to convert i t into benzophenylhydrazine with the object of characterising the latter and applying the isonitrile reaction to it. Benzopheny lhydrazine, The transformation of benzoaniline into the hgdrazine was effected by the reduction of the diazo-compound with stannous chloride.For this purpose 20 grams of the paramidobenzophenone were mixed with 400 grams of hydrochloric acid and the calculated quantity of sodium nitrite (9 grams) dissolved in water was gradually added to the well-cooled mixture ; an interval sufRcient foy the nitrous smell to disappear being allowed after each addition. When the diazotisation is complete the solution is filtered and the filtrate poured into a cold solution of 90 grams of stannous ohloride in 200 grams of hydro-chloric acid. The pale yellow precipitate which immediately appears is collected on a linen filter and dried on porous plates ; during the drying it gradually becomes orangc in colour. To obtain this hydrazine hydrochloride in a state of purity the orange powder is treated with hot water and the solution filtered when a con-siderable quantity of a yellow insoluble organic tin-compound is left on the filter.The water used must not be quite a t the boiling point, o r the hydrazine will be slightly decomposed. When concentrated hydrochloric acid is added to the warm filtrate faintly colourecl needles of the pure hydrazine hydrochloride are deposited which after drying in a vacuum gave on analysis numbers corresponding to the formula C6H4< (q-NK.NJ& - (1) -c 0 * (’6H5 ,H(-i1 .-Found. Calrulated for r-A- 7 C13H,:jN20Cl. I. 11. 111. N 11.27 11-68 11.55 -CI . . . 14-28 - - 13.98 The hydrochloride reduces Fehling’s solution dissolves readily in warm water and in alcohol but is insoluble in hydrochloric acid. The hydrazine sulphate may be prepared by the addition of dilute sulphuric acid to an ethereal solution of the base when it separates out in white needles easily soluble in water but readily decomposed by boiling.The hydraziiLe itself can only be prepared satisfactorily by the addition of a cuncentrated solution of sodium acetate to the slightl 6 1 d RUHEIIANN AND BLACKJIAN BENZOPI~ENPLHTDRAZISE. warm solution of the liydrocliloride when i t crystallises out in yellow needles. If the acetate be added to the very hot or boiling solution of the hydrochloride the base is then precipitated in a more or less resinous state. The hydrazine is fairly stable a t ordinary tempera-tures but a t 100" C. it gradually darkens with slight decomposition. It melts a t 127" is very soluble in alcohol ether and benzene but on evaporating the solut,ions i t is left behind as a resin.The crystals of the hydrazine obtained as above were prepared for analysis by washing with water and drying in a vacuum over sulpliuric acid. The formnla C t I < ) i ) ~ ~ ~ ~ ~ requires :-Found. Theory for r-J- v CI3HIP N,O. I. 11. 11 r. c 73.74 - - 73.53 H 5*i2; - - 5.36 N 13.20 - 13.52 13.23 Acetylbenxophenylli ydrazine.-Acetic anhydride acts on the hydrazine with evolution of heat. The reaction is completed on the water-bath, the crystalline product purified by treatment with animal charcoal, and recrystallised from hot watw. It forms white needles melting a t 154+-155O and easily soliible in alcohol ; i t gave on analysis values (1 j-CO*C,H, (4 j-NH-NHCO.CH,' corresponding to the formula Cs&< Found.Theory for r--L- 7 C16tllJ20 I. 11. C 70.87 70.72 -H . . 5.51 5.80 N 11.02 - 11-14 -Ben.zophenylseinical.baziJe is formed by adding an aqueous solutioa of potassium cyanate to a solution of the hydrazine hydrochloride. The resnlting precipitate crystallises from boiling water in which i t is difficultly soluble in slightlp coloured cr~stals which melt a t 21 5aq5" with decomposition and reduce Fehling's solution. Analpis gave numbers corresponding t o the formula (l)-CO*C,:H, C6H4< (4) -N H-NH-CO .NH; Found. 7 Theo1.y for (--L-C14H13N301. I. 11. C 66.10 - 65-88 H 5.10 5.37 N 16.47 -16.68 REHEJIANN ABD BLACKMAN BENZOPHENYLHYDRAZISE. 615 Bsnxophe~i~l-phenyls~ic~hosemica~ba~ide.-Ry adding phenyl mustard oil to an ethereal solution of the bydrazine a sulphosemicarb-xzide of the formula c6&< (4)-NH.NH.CS.NH.C,H5 is obtained.This after a short time separates out in yellow crystals difficultly soluble in hot alcohol from which on cooling they crystallise in plates melting a t 203" with decomposition. (I)-CO*C,H5 They gave on analysis the following results :-Pound. Calculated for -7 C,,Hl,N,OS. I. 11. N 12.10 19.31 S 9.22 9.47 --Benzopheny 1-tenzaldehy de hylhazine c6H4< (l)-CO*C,H (4)-NH,N:CH.C,H,, is obtained by adding to a warm solution of benzophenylhjdrazine hydrochloride a concentrated solution of sodium acetate and benzalde-liyde. Alcohol is subsequently added and the solution allowed to stand for some time when orange crystals separate out; these dis-solve with difficulty in hot alcohol and crystallise from i t in yellow glittering plates which melt a t 188".They gave on analysis-Found. Theory for f---7 €I 1 sN2O. I. 11. C 80.00 $0.20 H 5.52 .- 5.33 N 9.33 - 9.27 -( 1)-C O*C,H5 Benzophenylacetone hydraxifie c6H4< (4)-NH.N:C(CH,), is pre-cipitated from a solution of the hydrazine hydrochloride by the addi-tion of acetone and a conceritrated solution of sodium acetate. The precipitate is dissolved in hot dilute alcohol which on standing, deposits plates melting a t 125" and easily soluble in alcohol a n d acetone. This substance decomposes after being kept €or a few days a t ordinary temperatures. A nitrogen determination of this compound dried in a vacuum gave-Calculated for C16H16N20* Pound.N 11-11 11.09 (1)-co'c6H5 Acstophenone- benzoplieny Lhydrazine C&< H.N:C < CH is c6H5 prepared in a way quite analogous to that given aboye for the aceton 6 16 RUHEMANN AND BLACKMAN BESZOPHENYLI-IYDRAZINE. compound. a t 140-141". mination. It crystallises in bundles of yellow needles which melt Its composition was confirmed by a nitrogen deter-Theory for C21H1BN20' Found. N 8.937 9.08 When pyruvic acid is added to a warm aqueous solution of the liydrazine hydrochloride a lemon-yellow flocculent precipitate of this substance is a t once thrown down. It is soluble in dilute alcohol and crystallises from i t in tuftjs of curved needles which melt at 210" with decomposition. The following numbers correspond to the formula C,H,4N203 :-Found.7- 7 Theory. I. 11. 111. C 68-08 68.31 67.75 -H . . . . . . 4.96 5.90 5.19 -N . . . . . . 9.93 - - 10.14 This acid is easily soluble in alcohol in alkalis and ammonia. The barium salt is dissolved by hot water and crystallises from it in yellow needles. The silver salt is thrown down as a yellow precipi-tate on adding silver nitrate to ah ammoniacal solution of the acid. This salt rapidly decomposes and blackens on warming with water. The ethyl suZt of this acid is easily formed by heating together on a water-bath for 1-2 hours nine parts of absolute alcohol one part of concentrated sulphuric acid amd one part of the pyruvic acid compound in a flask connected with an inverted condenser.The ethereal salt is then precipitated by the addition of water washed with dilute ammonia to remove any unaltered pyruvic acid compound, and recrystallised from alcohol. The yellow needles thus obtained melt at 145" without decomposition. On analysis they gave numbers (l)-CO*C,H5 (4)-NH*N:C <gFo C2H corresponding to the formula CsH4< Found. Theory for --7 C,H,,N203. I. 11. C 69.68 69-73 -H 5-80 6.08 - 9.29 N . . 9.09 RUHEMANN ASD BLACKMAN BESZOPHEKYLHTDRAZINE. 61 7 BenzoincEoZecarboxyZic acid C6H5*CO*C,H,<,H>C*COOH CH is pre-pared by heating the finely powdered ethereal salt of benzophenyl-hydrazine-pyruvic acid with an equal weight of freshly fused zinc chloride at a temperature of 220" in an oil-bath. The mixture melts, darkens and froths briskly after two or three minutes at the end of which time the reaction is complete.When cool the resulting brown mass is powdered and warmed with very dilute hydrochloric acid to remove the zinc chloride. The dark-coloured substance that remains is with the exception of a little resin all dissolved by repeated extrac-tion with ether. The ethereal solution is then shaken with dilute soda from which on subsequent addition of hydrochloric acid the indolecarboxylic acid is thrown down as a yellow precipitate. TO purify this it is dissolved in ammonia and the solution boiled with animal charcoal; on addition of hydrochloric acid it yields a less coloured precipitate which readily dissolves in alcohol and crystallises out in yellowish needles. The acid may be obtained perfectly white, though with a considerable loss of material by boiling its alcoholic solution with animal charcoal filtering and concentrating the filtrate.The pure acid melts at 284-285" with decomposition. The formula C,sH,,N03 requires-Theory. Found. C . 72.45 72.23 H . 4.15 4.34 This acid is only slightly soluble in boiling water but dissolves readily in alcohol and in ammonia. The addition of silver nitrate to the latter solution throws down the silver salt as a yellowish, flocculent precipitate. When heated at a temperature between 280-290" it gives off carbonic acid and is transformed into benzo-indole. The latter was obtained in the form of neai-ly white needles melting at 144-145" by dissolving the melted product in alcohol and decolorising the alcoholic solution by animal charcoal.When dissolved in alcohol it colours pine shavings moistened with hydro-chloric acid violet and when acidulated with hydrochloric acid it is coloured red by potassium nitrite. We intend t o pursue the investigation of this compound. A small quantity of the ethyl salt of the benzoindolecarboxylic acid is contained in the ethereal solution of the product of the zinc chloride condensation and may be obtained as a yellow residue by evaporating the ether after the free acid has been removed by agitation with sodium hydroxide solution. This residue dissolved in alcohol boiled with animal charcoal and then concentrated yields VOL. LV. 2 618 DISON FURTHER STUDY OF THE THIOCARBIMIDES. slender needles which melt at 160-161".The quantity obtained was however too small to admit of verification by analysis. Action of Chloroform and Alcoholic Potash o n Benzophenylhydrazine. It was expected that chloroform and alcoholic potash would act on this hydrazine in a manner analogous to that of their action on phenylhydrazine and its homologues leading to the formation of a tetrazine as has been shown before (Zoc. cit.) and as will be further seen from a communication shortly to be made to the Society. But the desired compound could not be obtained. When an alcoholic solution of the hydrazine is treated with these agents it becomes first green and then deep-red in colour. The ethereal extract of the latter, when shaken with dilute sulphuric acid and then evaporated yields a red resin from which boiling water extracts a small quaiitity of a crys-talline compound probably formylbenzophenylhydrazine which is easily decomposed when boiled with water; the same compound appeared also to be formed by heating the hydrazine with formamide a t 140" till ammonia ceased to be evolved but owing to its easy decom-position it could not be recrystallised. All attempts to obtain a crystalline substance from the red resin left after extraction with water entirely failed. University Laboratory, Cambridge

ISSN:0368-1645    

DOI:10.1039/CT8895500612

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

618 DISON FURTHER STUDY OF THE THIOCARBIMIDES. LX1.-Further Study of the Thiocarbimides. By AUGUSTUS E. DIXON M.D. Assistant Lecturer in Chemistry, Trinity College University of Dublin. I N a recent communication (Trans. 1880 300) I described a number of substances obtained by the combination of certain thiocarbimides with primary and secondary amines and with phenylhydmzins. I hope shortly to describe a further investigation of the hydrazine class of compounds ; meanwhile in the present paper an account will be found-(a) of a number of disubstitu ted thiocarbamides hitherto wanting ; ( b ) of the combinations of certain thiocarbimides with piperidine ; and (c) of the relations between the thiocarbimides and thialdine DISON FURTHER STUDY OF THE THIOCARBIMIDES. 619 1.Methy lthiocarbirnide and Benxylaniine-~et7~lbenzylthiocarbamide. Pure benzylamine dissolved in alcohol was added to a warm alcoholic solution containing an equimolecular proportion of methyl-thiocarbimide. Heat was evolved and the pungent smell of the thiocarbimide disappeared. After several days' exposure to the air, the mixture assumed the consistence of a thin syrup from which aggregations of crystalline matter slowly separated. The latter were freed as far as possible from the syrupy mother-liquor by filtration under pressure and then recrystallised twice from benzene. The sub-stance is very freely soluble in this liquid when hot; but though it is somewhat sparingly so in the cold the crystallisation is rather tedious the solu ticin remaining sii persaturated for a considerable time.When purified as described it forms agglomerated masses of dense white octahedral crystals which melt between 74" and 74.5". A sulphur determination made by evaporating the substance to dryness with sodium hydroxide in a nickel crucible and fusing the residue with potassium nit,rate afforded 14.41 per cent. of sulphur ; theory for C9H,,N,S would require 17-79 per cent. This low result was rather unexpected as the process just indicated gives with suitable compounds very satisfactory results. It was found how-ever on further investigation that this part'icular compound is difficult of attack by alkalis even when the latter are concentrated ; the loss was therefore due presumably to the decomposition at a high temperature of a little unattacked thiocarbamide with evolution of volatile snlphuretted products.This difficulty was easily met by operating as follows :-0.2034 gram was oxidised with fuming nitric acid on the water-bath ; the oxidation-product evaporated to dryness introduced into a nickel crucible and again evaporated to dryness with sodium hydroxide. The residue fused with potassium nitrate gave 0.2604 gram BaS04, Or S = 17.60 per cent. Calculated for C,H1,N,S S = 17-79 ,, The action is thus represented :-Methylbenzylthiocarbamide when heated with water melts to somewhat dark-coloured droplets which just sink in the liquid. These dissolve to a slight extent and the clear solution on cooling, becomes milky from the separation of a cloud of minute oily globules, which after a t,ime solidify to octahedral crystals.It is extremely 2 x 620 DISO?; FUhTHER STUDY O F THE THIOCA4HIiIMIDES. soluble in alcohol ; moderately so in ether ; its solubility in benze has already been mentioned. Ammoiiiacal silver nitrate added to either the aqueous or alcoho solution gives an immediate black precipitate ; but it is curious note that just as in the case of the homologous ethylbenzylthi carbamide (described in the communication before referred to) t solution either in water or alcohol is not desulphurised even prolonged boiling with alkaline lead tartrate. This resistance desulphurisation is remarkable and recalls Lellmann’s observati (Annalen 221 8 ; 228 248) that boiling with alkaline lead sol tion fails to remove sulphur from the thiocarbamide-derivatives the orthodiamines e.g.CS<NH>CGH4. I am inclined to consider that the difficulty in withdrawing t sulphur under the conditions named is due in some way to the fa1 nature of both radicles. The data necessary to warrant a gene conclusion are for the most part only ohtainable by direct experime b u t those hitherto obtained seem to point to the view that in symmetrical disubstituted thiocarbamide desulphurisation by le hydrate is not effected where both radicles are of a fatty nature. ( the other hand if either or both of the radicles be non-fatty des? phurisation is easy. Thus diethylthiocnrbamide in either aqueous alcoholic solution is unaffected by boiling with iead hydrate (Hc mann Rer. 2 601). ‘I have also ascertained by direct experime that dibenzylthiocarbamide in alcoholic solution is not sensit desulphurised by boiling with alkaline lead solution.(It is desi phurised instantly and in the cold by ammoniacal silver nitrat1 Again as already recorded (Dixon Zoc. cit.) ethylbenzylthiocarbami doesnot yield its sulphur to alkaline lead tartrate even at the boili temperature. But on the substitution of either or both fatty groups by non-fai groups this resistance to desulphurisation seems to be removed. Thl I have found ethylphenyl- ethylorthotolyl- and (loc. cit. 302) benx, phenyl-thiocarbamides all easily desulphurisable ; and the same hol good (Hinterberger Annulen 83 346) for ethylallylthiocarbamic Further diphenyl- diorthotolyl- and (Bizio Jahr. 1861 49 allylphenyl-thiocarbanides all readlly give up their sulphur und the conditions named as does also (Zinin Annalen 84 346) all, a-naphth y 1 thiocarbami de.NH 2. Me th y lthiocar bintide and parato hidine-Met hy lparato ly 1 thio-carbamide. This substance-metameric with the preceding-was obtained mixing equimolecular proportions of methylthiocarbimide and pa DIXON FUETIIER STUDY OF THE THIOCARBIMIDES. 62 1 toluidine each dissolved in warm concentrated alcohol. After some time tufts of prismatic crystals began to crystallise out; when nothing further appeared to separate these were drained off washed, and recrystallised from boiling alcohol. As thus obtained the sub-stance forms beautiful vitreous prisms melting at 125-126" without decomposition. Sulphur was estimated with the following result :-0.2070 gram evaporated to dryness with sodium hydroxide and fused with potassium nitrate gave 0.2610 gram BaS04, Or S = 17.81 per cent.Calculated for C9H12NzS S = 17.79 ,, The action is thus formulated :-The yield amounted to nearly 70 per cent. of the theoretical. Methylparatolylthiocarbamide is slightly soluble in boiling water, almost insoluble in cold. It is moderately soluble in hot alcohol, and freely soluble in ether. Silver nitrate throws down a white precipitate which soon blackens ; the solution is also immediately desulphurised by boiling with alkaline lead tartrate (cf. methjl-benzylthiocarbamide) . 3. Methy 1 t hiocarbirnid e and Ort hoto hidine- Met hy 1 o r t hot o 1 y 1 t hio-carbamide. This substance-metameric with the two preceding compounds-was prepared by mixing the theoretic quantities of base and thiu-carbimide in concentrated alcoholic solution.No sensible heat was evolved but after a couple of days the mixture had solidified t o a pasty mass ; this was recrystallised three times from alcohol aftep which the substance separated in pearly-white flattened rhombic crystals. The latter melt without decomposition betweeen 152" and 153" that is to say 26" higher than the corresponding para-compound. When broken up the dry substance forms a lustrous flour-like white powder which on friction becomes strongly electrical the particles flying about in all directions. The formula was verified by a sulphur determination :-0.1808 gram fused with sodium hydroxide and potassium nitrate, afforded 0.2325 gram BadOd, Or S = 17.67 per cent.Calculrtted for CS<Na.c NI-I*CHs H S = 17.79 , 7 . 622 DIXON PULTHER STUDY OF THE THIO~I1liBI.\IIDES. The action is formulated as in the preceding case. The substance is somewhat soluble in boiling water easily soluble in hot alcohol moderately in the cold. Amrnoniacal silver nitrate added to a cold solution immediately precipitates silver sulphide and the solution is also tolerably readily desulphurised by boiling with a1 kaline lead tartrate. 4. A llylthiocarbimide and Orthotoluidine-Allylorthotoly lthiocarbamitle. Equirnolecular proportions of allylthiocarbimide and orthotoluidin e were mixed-each in concentrated alcoholic solution. No sensibl c evolution of heat was observed but after some days tufts of fine needles began to appear increasing in quantity until at last the cont,ents of the vessel formed a solid cake.This was removed, pressed and recrystallised three times from dilute spirit. The re-crystallisation is somewhat tedious the solutions having a tendency to remain supersaturated. Thiis purified the substance forms tufts of small white prisms melting between 75" and 76". A sulphur determination afforded the following result :-0.2806 gram treated with NaOH and RN03 yielded 0.2317 gram BaS04, Or S = 15-27 per cent. NHT H Calculat.ed for CS<NH.&:H S = 15.54 ,, Allylorthotolylthiocarbamide when heated with water melk to oily globules which sink in the liquid. These dissolve to a slight extent separating again for the most part as the solution cools, in finely-divided droplets which give the liquid a milky appearance ; after a time these droplets solidify to microscopic tufts of pointed prisms.The substance dissolves ereely in alcohol and ether and is soluble also in benzene and in light petroleum. Ammoniacal silver nitrate produces an immediate black precipitate in the cold; the sulphur is also readily removed by warming with nlkaline lead solu-tion with production of a brilliant speculum of galena. 5. Benzoylthiocarbimide and Orthotoluidine-Orthotolylbenxoy lthio-cnrbamide. Orthotoluidine was dissolved in alcohol the vessel cooled by im-mersion in water and to the solution a quantity of benzoylthio-carbimide was gradually added in accordance with the equation DIXON FURTHER STUDY OF THE THIOCARBIMIDEY.623 The substances combined vigorously and tufts of white prisms began a t once to separate; in a few minutes the contents of the vessel had set to a solid yellow mass. The latter on draining and washing with cold alcohol became almost white On recrystallisa-tion from boiling alcohol benzoy1orthot)olylthiocarbamide was obtained in long well-formed transparent prisms possessing a faint yellow tinge and melting between 118" and 119". Determination of sulphur :-0,1983 gram treated with NaOH and KN03 afforded 0.1773 gram BaSO,, Or S = 12-30 per cent. Calculated for C,,H,,N,SO S = 11.86 ,, The substance is insoluble in cold water moderately soluble in cold alcohol easily in hot. The solution is blackened immediately on addition of silver nitrate and is readily desulphurised by boiling with alkaline lead tartrate.Mercuric chloride added to the alcoholic solution gives a white curdy precipitate. 6. Benzoplthiocarbimide and Piperidine-P~peridylbei~zoylthiocarb-amide. Gebhardt (Ber. 17 3039) has described compounds of piperidine with methyl and some aromatic thiocarbimides. In order to ascer-tain whether the acid thiocnrbimide" would afford an analogous result the following experiment was made :-To 1 mol. prop. piperidine mixed with anhydrous benzene was added a benzene solution containing 1 mol. prop. of benzoylthiocarb-imide. The substances combined energetically the heat evolved being sufficient to boil off a portion of the benzene and the pungent bitter almond-like smell of the thiocarbimide vanished.The mixture was now exposed freely to the air in order to allow the residual benzene to evaporate. At the end of a fortnight there was no sign of crystallisation the syrupy liquid was therefore placed under the air-pump receiver where in a couple of days it solidified. The solid product recrystallised twice from spirit formed tine, silvery-white needles melting at 122-1'23" to a golden-yellow liquid. Analytical data :-* It is curious to note that benzoylthiocarbimide-obtained by Miquel ( A n n . Chim. Phys. [5] 11 300) by the action of benzoyl chloride upon lead thiocyanate-is always referred to as " benzo$thiocyanate." It is an undoubted thiocarbimidr , though differing in some respects (as I hope to show in a future communication) from the alkyl thiocarbimides 624 DIXON FURTHER STUDY O F THE THlOChRBIJlIDES.0.2060 gram burnt with CuO and copper gauze in front gave Or N = 11.34 per cent. 0.2075 gram treated with NaOH and KNO afforded 0.2040 gmm 19% C.C. nitrogen at 12” and 763 mm., BaS04, Or S = 13-51 per cent. Calciilated for C13H16N2SO. Experiment. N . 11.29 11.34 S 13.92 15.5 1 The following equation represents the action :-N K a C 0.C 6H5 CJL*CO*NCS + C,Hlo:NH = <N:C5H, Benzoylpiperidylthiocarbamide is insoluble in water soluble in alcohol and ether and freely soluble in benzene. The alcoholic solution gives with ammoniacal silver nitrate a white curdy preci-pitate partially soluble on heating. With alcoholic mercuric chlo-ride a white precipitate is thrown down ; and with ferric chloride a deep reddish-brown colour is produced.The alcoholic solution is not desulphurised by boiling with alkaline lead tartrate. Several attempts were made to obtain from acetylthiocarbimide and piperidine an analogous acetylated piperidylthiocarbamide. The substances combine energetically but no definite compound could be isolated though the conditions were varied i n sevei-a1 ways. It may be noted here that ctcetylthiocarbimide like the corresponding benzoyl-compound is commonly referred to as a thiocyanate ; in fact, Miquel the discoverer (loc. cit.) explicitly denies it admission to the class of t’hiocarbimides. But in some cases it certainly acts as a true ‘‘ mustard oil ; ” thus it forms disubstituted thiocarbamides with aniline the toluidines and a-naphthylamine ; and as I recently showed (Trans.1889 303) it also behaves as a thiocarbimide towards phenylhydrazine. 7. Ethylthiocarbimide and Piperidilze-Ethyl~iperid~lthiocarbumide. Alcoholic solutions of ethylbhiocarbimide and piperidine were mixed in quantities required by the equation-Heat was evolved and the combination was completed by warming on the water-bath until the mixture ceased to smell of the thiocarb DISON FURTHER STUDY OF THE THIOCARBIMIDES. 625 imide. On evaporation of the alcohol a brown oily liquid was left, which in about 10 days solidified t o a radiating crystalline mass melting between 44" and 46.5". The purification of the substance presented grcat difficulty; it is extremely soluble in alcohol ether, acetone chloroform amyl alcohol ethyl acetate benzene and carbon bisnlphide.It is sparingly soluble in water from which however it separates as an oily liquid which is still impure. On adding plntinic chloride t o the alcoholic solution an orange-brown platinum cornpound separated as an amorphous powder, which was washed well with spirit and dried over sulphuric acid. A quantity of this powder was suspended in water through which a current of snlphuretted hydrogen was passed but this treat-ment failed to separate the platinum even when the solution was heated to the boiling point. The crude substance was now finely ground washed well wif,h light petroleum in which it is insoluble and dried over sulphuric acid for analysis. 0.2084 gram burnt with CuO and copper gauze in front gave 28.3 C.C.nitrogen at 19" and 767 mm., Or N = 15-97 per cent. 0-1769 gram treated with I 3 " 0 3 * NaOH and KN03 gave 0.2411 Or S = 18-73 per cent. gram BaSO1, Calculated for C,H,GN&3. Experiment. N . 16-31 1 5 9 i S . . 18.61 18.i3 The analytical result is not very satisfactory as regards the nitrogen but there can be no doubt that the brown radiating, crystalline mass referred to above consists essentially of ethjl-piperidylthiocarbamide. Ammoniacal silver nitrate produces a yellow precipitate which blackens slowly on standing or instantly on heating. Like the preceding compound-benzoylpiperidylthiocarbamide-it is very stable towards alkaline solution of lead which fails to remove the sulphur even on boiling. This resistance to desulphurisation I have observed is also shared by phenylpiperidy lthiocarbamide,f-* Vide ante an eathation in which the treatment with nitric acid waa omitted, yielded only 11.9 per cent.of the sulphur. t This compound was first obtained by Gebhardt (Ber. 17 3039). A short account of it was subsequently published by Skinner and Ruhemann (Trana. 1888, 558) who appear to hare been unaware of Qebhardt's discovery 626 DIXON FURTHER STUDY OF THE THIOCARBIMIDES. which gives up its sulphur to alkaline lead tartrate only on prolonged boiling. The substance dissolves with decomposition in concentrated nitric acid with production of a dark green colour. Concentrated sulphuric acid also dissolves it on gentle warming ; the solution in this case is colourless. The formula commonly ascribed to thialdine, assumes it to be an imidic compound as Gcbhardt (loc.cit.) has shown that various imidic substances-for example metbylaiiiline, ethylaniline piperidine and conine-can combine with the thiocarb-imides to form substituted thiocarbamides I considered that i t would be interesting to ascertain whether under similar conditions the com-plex thialdine residue could be introduced. The results of Marckwald's experiments with thialdine thiocyanate" rendered it improbable how-ever that this would be the case. A. Orthotolylthiocarhimide and Thialdine. These substances in alcoholic solution were mixed in tions demanded by the equation-No sensible rise of temperature occurred but on slowly the propor-evaporating the alcohol tufts of needles formed in a brown smeary evil-smelling liquid.The former purified by recrystallisation from alcohol formed thin white needles melting at 157". A sulphur determination yielded 12.87 per cent. of S; the compound formulated above (tolylthialdylthiocarbamide) would require 30.7 per cent. The product is in fact diorthotolylthiocarbamide :-Calculated for CS(NH*C7H7)2. Experiment. S 12.51 12.87 M. p. of CS(NH.G) = 156 or 158" (Ber. 4 985; 12 1854; The experiment was now repeated using thiocarbanile. 2301). Found 157". * Marckwald (Be?. 19 1826) found that on boiling thialdine thiocyanate with water no thiocarbamide was produced ; but the substance decomposed into thio-aldehyde y-trithioaldehjde and a compound of the formula C,H9NS3 BESZYIA~I~IOSIUX SUCCISATES ASD THEIR DERIYATITES.627 B. PhenZ/ltli,iocnr~imide and Thialdive. Molecular proportions of these substances were mixed under the same conditions as in the previous case As the alcohol evapo-rated at the ordinary temperature leafy crystals separated the liquid becoming smeary and a t the same time acquiring a penetrating and very disgusting smell. The solid product recrystallised from alcohol formed pearly laminae melting at 152". These resembled thiocarbanilide (m. p. 153") in all respects tasting intensely bitter, and evolving the characteristic odour of thiocarbanile when boiled with concentrated hydrochloric acid. Similar experiments were made using ethyl- and allyl-thiocarbimides ; these afforded resul ts analogous to those already described. The doubling of the thiocarbimide radicle to form a symmetrical disubstitution-compound is remarkable and the more so since tlic processes were all carried out either a t the ordinary temperature of the air or a t a temperature very slightly above it. It would he interesting to ascertain what becomes of the thialdine residue ; in all four cases the bye-product had the same appearance-a somewhat yellowish sticky liquid-and the suggestion naturally offers itself that this might perhaps consist of a dithialdylthiocarbamide prodnced according to the equation-The liquid in question has however such a persistent and dis-gusting smell that I did not care to examine it further. Chemical Laborn t or y, University of D ~ b l in

ISSN:0368-1645    

DOI:10.1039/CT8895500618

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

BESZYIA~I~IOSIUX SUCCISATES ASD THEIR DERIYATITES. 627 LXI1.-Benzy lnmmonium Succinates and their Derivatives. Ry EMIL A. WERNER F.I.C. Assistant in the Chemical Laboratory of the University of Dublin. IN the course of a comparative study of the homologues of oxalic acid, to which my work on Chromoxalates (Trans. 1887 51 383 and 1888 53 404) led I noted incidentally that benzylammonium succi-nates and their derivatives are practically unknown. Hence when an opportunity lately presented itself I prepared a number of these compounds which are described below : 628 WERSER BEXZTLAMMONIUN SUCClNXTES 1. Normal Bentylanamonium Xuccinate. Di-benzylammonium succinate prepared by the neutralisation of a cold saturated aqueous solution of succiriic acid by pure benzyl-amine is soluble in all proportions in water and by the gradual evaporation of the solution a thick syrup is left which on standing over oil of vitriol ultimately solidifies to a confused semi-crystalline mass.The salt is also freely soluble in strong alcohol from which it is precipitated by ether as a thick syrup. However by very slow evaporation of its alcoholic solution it was obtained in the form of thin plates having a greasy lustre and unctuous to the touch. A determination of nitrogen in a specimen thus obtained gave the following result :-0.3335 gram gave 24.1 C.C. of nitrogen at 20" C. and 766 mm. or N = 8.29 per cent. The crystals of benzylammonium succinate so formed melt at 144-145" and at a higher temperature decompose into water SUC-cindibenzylamide and succinbenzylimide.2. Benzy lammonium Hydrogen Succinate. This salt was prepared by the addition of succinic acid (1 mol. prop.) to the aqueous solution of the normal succinate (1 mol. prop.). It is easily soluble i n water from which it crystallises readily i n thick vitreous somewhat elastic rectangular prisms ; by slow evaporation of their aqueous solution the crystals may be easily obtained of a considerable size. A specimen after powdering and drying by pressure between folds of bibulous paper gave the following analytical results :-0.2354 gram heated at 100-110" to a constant weight lost 02354 gram gave 11.3 C.C. nitrogen at 20" and 772.5 mm. or 0.0182 gram of H,O = 7.73 per cent. N = 5.55 per cent. Theory for COO .N Ha. CiH;,H,O. Found.C,H4 <coos H,O 7.73 per cent. 7-40 N 5-55 , 5.76 Benzylammnnium hydrogen succinate crystnllises therefore from wa.ter as a monohydrate. The anhydrous salt melts a t 116-117" ASD THEIR DERIVhTIVES. 629 This compound which is also produced by the rapid distillation of the benzylammoninm succinates is best prepared by the action of benzyl chloride on a mixture of succinimide and potassium or sodium hydroxide dissolved in strong alcohol. The equation representing its formation is-+ HZO + KCl. On account of secondary actions resulting in the production of small quantities of benzyl alcohol benzyl ethyl oxide and potassium succinamate the yield of the succinbenzylimide never rises above 60 per cent. of the theoretical. Succinbenzylimide crystnllises from alcohol by spontaneous evapora-tion in large brilliant flat six-sided prisms which melt at 98-99'.The following analytical data were obtained from a specimen twice crystallised from alcohol :-0.4426 gram gave 28.2 C.C. nitrogen at 16" and 767.5 mm. or 0.252 gram burnt with lead chromate gave 0.6446 gram CO and N = 7.45 per cent. 0.1326 gram H,O. Theory for ClIHl1NO2. Found. C. 69.84 per cent. 65-77 N 7-40 , 7.45 0 16.94 , (bydiff.) 16.80 H . 5-82 , 5-98 For the preparation of this compound and isolation of the secondary products the following method of working gave the best results :-To 50 grams of succinimide and 28 grams of potassium hydroxide, both dissolved in about 300 C.C. of strong alcohol 63 grams of benzyl chloride was added and the mixture digested on the water-bath with reversed condenser until potassium chloride ceased to separate ; for the above quantities from four to aix honrs' digestion proved sufficient." As the liquid cooled the new compound separated in beautiful crystals embedded in the potassium chloride the super-* By using a layge rounded conical flask and maintaining the water outside con-siderably above the level of the liquid within the boiling may be carried on without interruption 630 RKRXER BEKZYLAMMONIUM SUCCTKATES natant liquid was poured off and the mixture of chloride and crystals thrown on the filter-pump and washed with alcohol.From the crystals the chloride was readily removed by shaking with water. Only one other crop of crystals can generally be obtained by distillation of the mother-liquor for on concentration the succin-benzylimide ceases to separate in the crystalline form ; if the solution be now distilled as far as possible on the water-bath and the residue shaken up with water an oil is precipitated and separated; the aqueous solution is shaken up with ether and the latter is added to the oil; from this ethereal liquid a third crop of crystals of the succinbenzylimide separates on standing.The aqueous extract of the oil contains any excess of succiriimide with a small quantity of potassium succinamate formed during the reaction. The ethereal solution is then distilled until the temperature reaches about 220". The portion collected between 170-210" affords small quantities of benzgl alcohol (b. p.2 0 4 O ) and benzyl ethyl oxide (b. p. 185"). The residue iu the retort consists of impure succinbenzylimide, which may be obtained either by further distillation or by dissolution in chloroform or benzene and gradual precipitation of the solution by light petroleum. Succinbenzylimide is a very stable compound and distils undecom-posed between 390" and 400". It is easily soluble in alcohol very freely in chloroform and hot benzene moderately soluble in ether sparingly soluble in cold carbon bisnlphide more freely iu hot and insoluble in light petroleum ; it is moderately soluble in boiling water from which it is almost com-pletely precipitated on cooling in the form' of long thin iridescent plates. When boiled for several hours with alcoholic solutions of caustic potash and soda it is completely decomposed into bensylamine and succinic acid; it undergoes the same decomposition much more readily by heating with fuming hydrochloric acid in a sealed tube at 145-150" for one hour; on the other hand heating with fuming hydrochloric acid under the ordinary pressure does not affect the decomposition even after several hours' boiling.4. Succinbenzylumic Acid CzH,<cOO1l CO.NH-CH,.C,H, This compound is prepared by boiling the imide (2 mol. props.) with an aqueous solution of 1 mol. prop. of barinm hydroxide. The reaction which consists in an assimilation of a single molecule of water by the imide is complete after 5-10 minutes' boiling ; o ASD THEIR DERIVATIVES. 631 adding dilute hydrochloric acid to the product the new acid is im-mediately precipitated in thick white flocks and after washing on a filter is purified by recrystallisation from alcohol from which it readily separates in very fine large flat oblique prisms.These melt at 139" when pure. A specimen purified by recrystallisation from alcohol and dried at 100" gave the following analytical results :-0.2478 gram gave 13.8 C.C. of nitrogen at 13" and 771 mm. 0.2635 gram gave 0.6145 gram CO and 0.156 gram H,O. Theory for CllH13N03* Found. C 63.76 per cent. 63.60 H 6.28 , 6.57 N 6.76 , 6.64 0 23-20 , 23.19 (by diff.) Succinbenzylamic acid is somewhat soluble in boiling water almost insoluble in the cold arid slightly soluble in boiling benzene from which it separates completely on cooling in microscopic needles ; it is freely soluble in acetone almost insoluble in ether and carbon bisulphide.I t is not decomposed by heating with water alone in a sealed tube to 200". The silver salt is precipitated on addition of silver nitrate to an aqueous solution of the barium salt; when dried it forms a light, crystalline micaceous powder possessing a pearly lustre :-0.292 gram gave on ignition a residue of silver = 0.1001 gram. Theory for Found. CIlH12N03Ag. A g . . 34% per cent. 34.39 I t is insoluble in water or alcohol. The barium salt crystallises from water in rosette-like aggregates of A specimen dried by pressure Theory for (CliH,,N0&Ba = 24.95 per small prisms having a pearly lustre. and air exposure gave :-Ba = 25.02 per cent. cent.Ba. CO-NH-CH *C H 5. Succind L t enzy Zanzide C,H,< OBN H cHi. c6 H5. 6 6 For the preparation of this compound 10 grams of ethyl succinate were heated in alcoholic solution with 12.5 grams of pure benzylamine for several hours. The diamide separates from its alcoholic solution 632 WERNER BENZYLAMJIONIUM SUCCISATES on coolinq in thin crystalline plates possessing a very brilliant lustre ; these melt a t 205-206". The following analytical data were afforded by a well-crystallised specimen :-0.2776 gram gave 23 C.C. of nitrogen at 14" and 7.56.6 mm. 0.2384 gram gave 0.636 gram CO and 0.1520 gram HzO. The yield is nearly theoretical. Theory for C,BH,N202. Found. 0 . 72-97 per cent. 72.75 H . 6.75 , 7.08 N . 9-45 , 9-64 0 . 10.83 10.53 (by diff.).Succindibenzylamide is sparingly soluble in hot or cold ether, sparingly soluble in chloroform almost insoluble in carbon bisul-phide slightly soluble in boiling benzene insoluble in the cold and insoluble in water. It is not decomposed by boiling with aqueous soda. Unsuccessful attempts were made to obtain a mercurial or silver derivative of this diamide ; freshly precipitated mercuric oxide is not acted upon by the boiling alcoholic solution of the amide. CO.NH.CH,*C,H, 6 . SzLccinntonobe.lzzylamide C2H,< CO*NH, This amide is formed by the action of ammonia on succinbenzyl-imide thus :-For this purpose the succinbenzylimide is heated at 100" for 6-43 hours in a sealed tube with an excess of a strong solution of ammonia in alcohol. Under these conditions the yield of the amide never exceeds 30-34 per cent.of theory and even when the temperature is carried to 200" and maintained for several hours the yield is not materially increased. In order to separate the amide the contents of the tube are evaporated t o dryness on the water-bath and the solid residue is digested with chloroform which readily dissolves the unaltered imide, leaving behind the amide ; the latter is purified by dissolution in boil-ing alcohol from which it separates on cooling in glistening micro-scopic prisms which melt at 189". A specimen after drying at loo" gave the following result : AYD THEIR DERIVATIVES. 633 0.1911 gram gave 22.8 C.C. of nitrogen a t 20" and 769 mm. Theory for CO*NH*C,H, CPH4<CO.N& Found. N .. . . . . . . 13.59 per cent. 13.61 per cent. Succinmonobenzylamide in its behavioiir towards solvents re-scmbles the diamide from which it is readily distinguished by the ewe with which it gives off ammonia on boiling with fixcd alkali. On heating it first melts and a t a higher temperature parts with ammonia. regenerating the imide. The following comparatively easy decompositiorr of normal benzyl-ammonium succinate is worthy of note. A small quantity of tche syrupy mother-liquor from some di-benxylammonium succinate was evaporated in a glass dish on the water-bath as far as possible dried for a couple of hours in a water-oven and placed in a desiccator over oil of vitriol where it remained untouched for about seven weeks. On attempting to redissolvc the product in water it was found that a portion representing about 'LO per cent.of the whole refused to dissolve. This was collected, washed and crystallised from hot alcohol in which it was easily soluble. The crjstals which separated were easily seen to be a mixture of two compounds and the melting point 196" did not agree with any compound described in this paper. The crystals were directly digested with chloroform and a rather sharp separation was thus effected the products* so obtained gave the following results :-I. Product insoluble i n chloroEorm ; m. p. 205-206". 0.1864 gram gave 16 C.C. of nitrogen a t 180" C. and 762 mm. 11. Product soluble in chloroform and left as residue on erapora-0-1956 gram gave 13.4 C.C. nitrogen at 17" C. and 760.5 mm. or N = 9.88 per cent. ticn ; m. p. 102-103". N = 7.91 per cent. Succindibenzy lamide. I. Found. M. p. 2c)5-206" M. p. 205-206". N . . . . . . . . 9.45 per cent. 9.88 per cent. Snccinbenzylimide. TI. Found. M. p. 99" C. M. p. 102-1103". N . . . . . . . . 7.40 per cent. 7.91 per cent. * The quantity of materia.1 a t my disposal was too small to attempt B further purification. VOL. LV. 2 634 MENDELEEFF THE PERIODIC LAW Considering that the compounds were D o t quite pure the analytical results and melting points leave no doubt as to their identity. A few hours’ heating in the water-oven and exposure for several weeks over oil of vitriol were therefore sufficient to cause a partial loss of the elements of water and benzylamine from anhydrous benzylammonium succinat,e and the production of a mixture of the amide and imide. Universihy Laboratory, Trinity College Dublin

ISSN:0368-1645    

DOI:10.1039/CT8895500627

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

634 MENDELEEFF THE PERIODIC LAW LXII1.-The Periodic Law of the Chemical Elements. By Professor MENDEL~EFF. (FARADAY LECTURE delivered before the Fellows of the Chemicai Society in the Theatre of the R20yal Institution on Tuesday June &h 1889.) TEE high honour bestowed by the Chemical Society i n inviting me to pay a tribute to tahe world-famed name of Faraday by delivering this lecture has induced me to take for its subject the Periodic Law of the Elements-this being a generalisation in chemistry which has of late attracted much attention. While science is pursuing a steady onward movement it is con-venient from time to time to cast a glance back on the route already traversed and especially to consider the new conceptions which aim at discovering the general meaning of the stock of facts accumulated from day to day in our laboratories.Owing to the possession of laboratories modern science now bears a new character quite unknown not only to antiquity but. even t o the preceding century. Bacon’s and Descartes’ idea of submitting the mechanism of science simnl-taneouely to experiment arid reasoning has been fully realised iu the case of chemistry it having become not only possible but always customary to experiment. Under the all-penetrating control of experiment a new theory even if crude is quickly strengthened, provided it be founded on a sufficient basis; the asperities are removed it is amended by degrees and soon loses the phantom light of a shadowy form or of one founded on mere prejudice; it is able to lead to logical conclusions and to submit to experi-menha1 proof.Willingly or not in science we all must submit no OF THE CHEMICAL ELEMENTS. 635 t o what seems to us attractive from one point of view or from another, but to what represents an agreement between theory and experiment ; in other words to demonstrated generalisation and to the approved experiment. Is it long since many refused to accept the generalisa-t,ions involved in the law of Avogadro and Amphre so widely ex-tended by Gerhardt ? We still may hear the voices of its opponents ; they enjoy perfect freedom but vainly will their voices rise so long as they do not use the language of demonstrated facts. The striking observations with the spectroscope which have permitted us to arialyse the chemical constitution of distant worlcls seemed at first, applicable to the task of determining the nature of the atoms them-selves ; but the working out of the idesin the laboratory soon demon-strated that the characters of spectra are determined-not directly by the atoms but by 1,he molecules into which the atoms are packed ; and so it became evident that iiiore verified facts must be collected before it will be possible to formulate new generalisations capable of taking their place beside those ordinary ones based upon the con-ception of simple bodies and atoms.But as the shade of the leaves and roots of living plants together with the relics of a decayed vegetation favour the growth of the seedling and serve to promote its luxurious development in like manner sound gexieralisations-together with the relics of those which have proved to be untenable -promote scientific productivity and ensure the luxurious growth of science under the influence of rays emanating from the centres of scientific energy.Such centres are scientific associations and societies. Before one of the oldest and most powerful of these I am about to take the liberty of passing in review the 20 Sears’ life of a generalisation which is known under the name of the Periodic Law. It was in March 1869 that I ventured to lay before the then youthful Russian Chemical Society the ideas upon the same subject, which I had expressed in my just written “ Principles of Chemistry.” Without entering into detaiis I will give the conclusions I then arrived at in the very words I used:-“ 1.The elements if arranged according to their atomic weights, exhibit an evident periodicity of properties. “ 2. Elements which are similar as regards their chemical properties have atomic weights which are either of nearly the same value (e.g., platinum iridium osmium) or which increase regularly (e.g. potas-sium rubidium cmium). “3. The arrangement of the elements o r of groups of elements in the order of their atomic weights corresponds to their so-called calmcies as well as to some extent to their distinctive chemical properties-as is apparent among other series in that of lithium, beryllium barium carbon nitrogen oxygen and iron. 2 r G3G MENDELI~EZI'F THE PERIODIC LAW '' 4. The elements which are the most widely diffused have snintl atomic weights.' 6 5. The magnitude of the atomic weight determines the character of tho element just as the magnitude of the molecule determines the character of a compound body. ( 6 6 . We must expect tlie discovery of many yet unknown elementp, for example elements analogous t o aluminium and silicon whose atomic weight would be between 65 and 75. (' 7. The atomic weight of an element may sometimes be amended by knowledge of those of the contiguous elements. Thus the atomic weight of tellurium must lie between 123 and 126 and cannot be 128. " 8. Certain characteristic properties of the elements can be foretold from their atomic weights. " The aim of this communication will be fully attained if I succeed in drawing the attention of investigators to those relations which exiRt between the atomic weights of dissimilar elements which as far as T know have hitherto been almost completely neglected.I believe that the solution of some of the most important problems of our science lies in researches of this kind." To-day 20 years after the above conclusions were formulated! they may still be considered as expressing the essence of the now well-known periodic law. Reverting to the epoch terminating with the sixties it is proper to indicate three series of data without the knowledge of which the periodic law could not have been discovered and which rendered its appearance natural and intelligible. In the first place,.it was a t that time that) the numerical value of atomic weigh& became definitely known.Ten years earlier such knowledge did not exist as may be gathered from the fact that in 1860 chemists from all parts of the world met a t Karlsruhe in order to come to some agreement if not with respect to views relating to atoms at any rate as regards their definite representation Many of those present probably remember how vain were the hopes of coming to an understanding and how much ground was gained a t that Congress by the followers of the unitary theory so brilliantly repre-sented by Cnnnizzaro. I vividly remember the impression produced by his speeches which admitted of no compromise and seemed to advocate truth itself based on the conceptions of Avogadro, Gerhardt and Regnault which a t that time were far from being generally recognised. And though 110 understanding could be arrived at yet the objects of the meeting were attained for the ideas of Cannizzmo proved after a few years to be the only ones which could stand criticism mid which represented an atom as-" th OF’ ‘lXE CIIEMIZAL ELEMENTS.6 3 i sniallest portioii of an element which enters into a molecole of its compound.” Only such real atomic weights-not conventional ones -could afford a basis for generalisation. It is sufficient by way of example to indicate the following cases in which the relation is seen a t once and is perfectly clear:-K = 3 9 R b = 85 Cs = 133 Ca - 40 Sr = 87 Eia = 137 whereas with the equivalents then in use-K = 3 9 Rb = 85 Cs = 1%3 Ca = 20 S r = 43-5 Ba = 68.5 the consecutiveness of change i n atomic weight which with the true values is so evident completely disappears.Sesondly it had become cvident during t’he period 1860-70 and even during the preceding decade that the relations between the atomic weight’s of analogous elements were governed by some general and simple laws. Cooke Cremers Gladstone Gmelin Lenssen, Pettenkofer and especially Dumas had already established many facts bearing on that view. Thus Dumas compared the following groups of analogous elements with organic radicles-Diff. Diff. Diff. Diff. 18 0 = 8 S = 16’ Be = 40 144 P = 31 AS = 75’ Bi = 207j2 44 %e = 64 t 8 )3 x 8 Mg = 12 Ca = 20) Sr = 44 Sb = 119 Ba = 68 }3 x 8 )3 x 8 >& Li = ’Z}16 Na = 23 3 x a g = 39116 and pointed out some really striking relationships such as the fol-lowing :-F = 19.C1 = 35:5 = 19 + 1.6.5-Br = 80 I = 127 = 2 x 19 + 2 x 16.5 + 9 x 28. = 29 + 2 X. 16.5 + 28. A. Strecker in his work “ Theorien und Experimente m r l3estiru-mung der Atomgewichte der Elemente ” (Braunschweig 1859) after summarising the data relating to the subject and pointing out the remarkable series of equivalents-remarks that ‘‘ It is hardly probable that all the above-mentione 638 MESDEL~EFF THE PERIODIC LAW relations between the atomic weights (or equivalents) of chemically analogous elements are merely accidental. We must however leave t o the fut’ure the discovery of the law of the relations which appears in these figures.” * In such attempts a t arrangement and in such views are to be recognised the real forerunners of the periodic law ; the ground was prepared for it between 1860 and 1870 and that it vas not ex-pressed in a determinate form before the end of the decade may, I suppose be ascribed to the fact that only analogous elements had been compared.The idea of seeking for a relation between the atomic weights of all the elements was foreign to the ideas then current so that neither the uis tellurique of De Chancourtois nor the law of octuves of Newlands conld secure anybody’s attention. And yet 110th De Chancourtois and Newlands like Dumas and Strecker more than Lenssen and PettenkoEer had made an approach to the periodic law and had discovered its germs. The solution of the problem advanced but slowly becatwe the facts and not the law stood foremost in all attempts ; and the law could not awaken a general interest so long as elements having no apparent connection with each other were included in the same octave as for example:-1st octave of 7th Ditt,o I Newlands co & Nr Pt & Ir [ gL 1 Se .I R h F R u 1 gt I k~ I 0 s or Th 1 Analogies of the &hove order seemed quite accidental and the more so as the octave contained occasionally 10 elements instead of eight, and when two such elements as Ba and V Co and Ni or Rh and Ru, occupied one place in the octave.? Nevertheless the fruit was ripen-ing and I now see clearly that Strecker De Chancourtois and New-lands stood foremast in the way towards the discovery of the periodic law and that t,hey merely wanted the boldness necessary to place the whole question a t such a height that its reflection on the facts could be clearly seen.A third circumstance which revealed the periodicity of chemical elements was t’he accumulation by t h e end of the sixties of new information respecting the rare elements disclosing their many-sided relations t o the other elements and to each other. The * ‘< Es ist wohl kaum anzunehmen dass nlle im Vorhergehenden hervorgehobenen Beziehungen zwischen den Atomgewichten (oder Aequivalenten) in chemischen Verhaltnissen einander ahnliche Elemente b l o s zufallig sind. Die Auffindung der in diesen Zahlen gesetzlichen Bcziehungrn miissen wir jedoch der Zukunft iiberlassen.” -f To judge from J. A. R. Newllands’ work 0% the Discorery of the Periodic Law London 1884 p. 149 ; “ On the Law of Octaves ” (from the Chemical News, 12 83 August 18 1865) OF THE CIIEMICAL ELEMENTS.639 reseayches of Marignnc on niobium and those of Roscoe 011 vana-dium were of special momeut. The striking analogies between Yanadium and phosphorus on the one hand and between vanadium and chromium on the other which became so apparent in the investi-gations connected with that element naturally induced the corn-parison of V = 51 with Cr = 52 Nb = 94 with Mo = 96 and TE = 192 with W = 194; while on the other hand P = 31 could be compared with S = 32 As = 75 with Se = 79 and Sb = 120 with Te = 125. From such approximatioiis there remained but one step to the discovery of the law of periodicity. The law of periodicity was thus a direct outcome of the stock of generalisations and established facts which had accumulated by the end of the decade 1860-1870 it is an embodiment of those data in :L more or less systematic expression.Where then lies the secret of the special importance which has since been attached to the periodic law and has raiscd it to the position of a generalisation which has already given to chemistry unexpected aid and which promises to be far more fruitful in the future and to impress upon several branches of chemical research a peculiar and original stamp ? The remaining part of my communication will be an attempt to answer this question. I n the first place we have the circumstance that as soon as the I:tw made its appearance it demanded a revision of many facts which were considered by chemists as fully established by existing ex-perience.I shall return later on briefly t o this subject hut I wish now to remind you that. the periodic law by insisting on the necessity iur a revision of supposed facts exposed itself a t once to destruction i n its very oiaigin. Its first requiremetits however have been almost entirely satisfied during the last '20 years ; the supposed facts have yielded to the law thus proving that the law itself was a legitimate induction from the verified facts. But our inductions from data have often to do with such details of a science so rich in facts that only generalisations which cover a wide range of important phenomena can attract general attention. What were the regions t,ouched on by the periodic law ? The most important point to notice is that periodic fumtions used for the purpose of expressing changes which are dependent on rarin-tions of time and space have been long known.They are familiar to the nlittd when we have to deal with motion in closed cycles or with any kind of deviation from a stable position such as occurs in 1 wndulum-oscillations. A like periodic function became evident in tlie case of the elements depending on the maw of the atom. The primary conception of the masses of bodies or of the masses of atoms belongs to a category which the present state of science forbids us to discuss because as yet we have no means of dissecting o r This is what we shall now consider 640 MEXDEL~EFF THE PERIODIC LAW analysing the conception. All that was known of functions dependent on masses derived its origin from Galileo and Newton and indicated that such functions either decrease o r increase with the increase of mass like the att,raction of celestial bodies.The numerical expression of the phenomena was always found to be proportional to thc mass and in no case was an increase of mass followed b j a recur-rence of properties such as is disclosed by the periodic law of the elements. This constituted such a novelty in the study of the pheno-mena of nature that although i t did not lift the veil which conceals the true conception of mass it nevertheless indicated that the ex-planatmion of that conception must be searched for in the masses of the atoms ; the more so as all masses are nothing but aggregations, 01’ additions of chemical atoms which would be best described as chemical individuals.Let me remark by the way that though the Latin word “individual” is merely a translation of the Greek word ‘‘ atom,” nevertheless history and custom have drawn so sharp a dis-tinction between the two words and the present chemical conception of atoms is nearer to that defined by the Latin word than by the Greek, although this latter also has acquired a special meaning which was unknown to the classics. The periodic law has shown that our chemical individuals display a harmonic periodicity of properties dependent 011 their masses. Now natural sciome has long been accustomed to deal with periodicities observed in nature to seize them with the vice of mathematical analysis to submit them to the rasp of experiment.And these instruments of scientific thought would surely long since have mastered the problem connected with the chemical elements were i t not for a new feature which was brought to light by the periodic law and which gave a peculiar and original character to the periodic function. If we mark on an axis of abscissae a series of lengths proportional to angles and trace ordinates which are proportional t o sines or other trigouometrical functions we get periodic curves of a harmonic character. So it might seem at first sight that with the increase of atomic weights the function of the properties of the elements should also vary in the same harmonious way. But in this case there is no such continuous change as in the curves just referred to because the periods do not contain the intinite number of points constituting a curve but a cfiiiite number only of such points.An example will better illustrate this view. The atomic weights-Ag =’ 108 Cd = 112 I n = 113 Sn = 118 Sb = 120 Te = 125 I = 127 steadily increase and their increase is accompanied by a modificat,ion of many propertios which constitutes the essence of the periodic law OF THE CHEMICAL ELEMENTS. 641 Thus for example the densities of the above elements decrease steadily being respectivelj-10.5 8.6 7.4 7.2 6.7 6.4 4.9 while their oxides contain a n increasing quantity of oxygen :-AgzO Cd,O In2O3 Sn204 Sb,O Te206 120, But to connect by a curve the summit,s of the ordinates expressing any of these properties would involve the rejection of Dalton’s law of multiple proportions.Not only are there no intermediate elements between silver which gives AgCl and cadmium which gives CdC12, but according to the very essence of the periodic law there can be none ; in fact a uniform curve would be inapplicable in such a case as it would lead us to expect elements possessed of special properties at any point of the curve. The periods of the elements have thus a character very diffwent from those which are so simply represented by geometers. They correspond to points to numbers to sudden changes of the masses and not to a continuous evolution. In these sudden changes destitute of intermediate steps or positions in the absence of elements intermediate between say silver and cadmium or aluminium and silicon we must recognise a problem to which no direct application of the analysis of the infinitely small can be made.Therefore neither the trigonometrical functions proposed by Ridberg and Flavitzky nor the pendulum-oscillations suggested by Crookes, n9r the cubical curves of the Rev. Mr. Haughton which have been pro-posed for expressing the periodic law from the nature of the case, can represent the periods of the chemical elements If geometrical analysis is to be applied to this subject it will require to be modified i n a special manner. It must find the means of representing in a special way not only such long periods as that comprising, R Ca Sc Ti V Cr Mn F e Co Ni Cu Zn Ga G As Se Br, Na Mg A1 Si P S C1. In the theory of numbers only do we find problems analogous to ours and two attempts a t expressing the atomic weights of the elements by algebraic formule cieem to be deserving of attention, although neither of them can be considered as a complete theory nor as promising finally to solve the problem of the periodic law The attempt of E.J . Mills (1886) does not even aspire to attain this end. He considers that all atomic weights can be expressed by a logarithmic function, 15(n - 0*93i5t), but short periods like the following: 642 MESDEL~EFF THE PERIODIC LAW in which the variables n and t are whole numbers. Thus for oxygen, 12 = 2 and t = 1 whence its atomic weight is = 15.94; in the case of chlorine bromine and iodine n has respective values of 3 6 and 9 while t = 7 6 and 9 ; in the case of potassium rubidium and caesium n = 4 6 and 9 and t = 14 18 and 20.Its author places the problem of the periodic law in the first rank but as yet he has investigated t.he alkaline metals only. Tchitchhrin first noticed the simple relations existing between the atomic volumes of all alkaline metals ; they can be expressed according to his views, by the formula where A is the atomic weight and 3~ is equal to 8 for lithium and sodium to 4 for potassium to 3 for rubidium and to 2 for caesiun. If n remained equal t o 8 during the increase of A then the volume would become zero at A = 46$ and it would reach its maximum at A = 23+. The close approximation of the number 465 to the differences between the atomic weights of analogous elements (such as Cs - Rb I - Br and so on) ; the close correspondence of the number 33+ t o the atomic weight of sodium; the fact of n being necessarily a whole number and several other aspects of the ques-tion induce Tchitcbbrin to believe that they afford a clue to the uiiderstanding of the nature of the elements ; we must however, await the full development of his theory before pronouncing judg-ment on it.What we can a t present only be certain of is this that attempts like the two above named must be repeated and multi-plied because the periodic law has clearly shown that the masses of the atoms increase abruptly by steps which are clearly connected in some way with Dalton’s law of multiple proportions ; and because the periodicity of the elements finds expression in the transition from RX to RX, RX, RX4 and so on till EX, a t which point the energy of the combining forces being exhausted the series begins anew from RX to RX2 and so on.While connecting by new bonds the theory of the chemical elements with Dalton’s theory of multiple proportions or atomic structure of bodies the periodic law opened €or natural philosophy a new and wide field for speculation. Kant said that there are in the world “ two things which never cease to call for the admiration and rever-ence of mail the moral law withill ourselves and the stellar sky above us.” But when we turn our thoughts towards the nature of the elements and the periodic law we must add a third subject, namely “the nature of the elementary individuals which we discover everywhe~e around us.” Without them the stellar sky itself is iuconceivable; and in the atoms we see a t once their peculiar indi-Another attempt was made in 1888 by B.N. Tchitchdrin. A(2 - 0*00535A7~) OF THE CHENICXL ELEMENTS. 643 vidualities the infinite multiplicity of the individuals and the sub-mission of their seeming freedom to the general harmony of Nature. Having thus indicated a new mystery of Nature which does not yet yield to rational conception the periodic law together with the yerelations of spectrum analysis have contributed to again revive an old but remarkably long-lived hope-that of discovericg if not by experiment a t least by a mental effort the primary wzutter-which had its genesis in the minds of the Grecian philosophers, and has been transmitted together with many other idem of the classic period to the heirs of their civilisation.Having grown during the times of the alchemists up t a the period when esperirnental proof was required the idea has rendered good service; it induced those careful observations and experiments which later on called into being the works of Scheele Lavoisier Priestley and Cavendish. It then slumbered awhile but was soon awakened by the attempts either to confirm or to refute the ideas of Prout as t o the multiple proportion relationship of the atomic weights of all the elements. And once again the inductive or experimental method of studying Nature gained a direct advantage from the old Pythagorean idea: because atomic weights were determined with an accuracy formerly nnknown. But again the idea could not stand the ordeal of experi-mental test yet the prejudice remains and has not been uprooted, even by Stas; nay it has gained a new vigour for we see that all which is imperfectly worked out new and unexplained from the still scarcely studied rare metals to the hardly perceptible nebulee, have been used to justify it.As soon as spectrum analysis appears as a new and powerful weapon of chemistry the idea of a primary matter is immediately attached to it. From all sides we see attempts to constitute the imaginary substance helium' the so much longed for primary matter. No attention is paid to the circumstaiice that the holium line is only seen i n the spectrum of the solar protube-rances so that its universality in Nature remains as problematic as the primary matter itself; nor to t b e fact that the helium line is wanting amongst the Fraiinhofer lines of t h e solar spectrum and thus does not answer to the brilliant fundamental conception which gives its real force to spectrum analysis.And finally no notice is even taken of the indubitable fact that the brilliancies of the spectral lines of the simple bodies vary under different temperatnres and pressures ; so that all probabilities are in favour of the helium line simply belonging to some long since khown element placed under suoh conditions of temperature pressure and gravity as hare not yet been realised in our experiments. Again the idea that the excellent investigations of Lockyer of the spectrum of * That is a body having a wave-length equal to OQOO5S75 millimetre 644 MENDELBEFF THG PERIODIC LAW iron can be interpreted i n favour of the compound nature of that element evidently must have ayisen from some misunderstandillg.The spectrum of a compound body certainly does not appear as a suru of the spectre of its components ; and therefore the observations of Lockyer can be considered precisely as a proof that iron undergoes no other changes a t the temperature of the sun but those which i t experiences i n the voltaic arc-provided the spectrum of iron is pre-served. As to the shifting of some of the lines of the spectrum of iron while the other lines maintain their positions it can be explained as shown by M. Kleiber (Journal of the Russiaw Chemical and YJtysical Society 1885,147) by the relative motion of the various strata of the sun’s atmosphere and by Ziillner’s laws of the relative brilliancies of different lines of the spectrum.Moreover i t ought not to be forgotten that if iron were really proved to consist of two or more unknown elements we simply should have an increase of the number of our elements-not a reduction and still less a reduction of all of them to one single primary matter. Peeling that spectrum analysis will not yield a support to the Pythagorean conception its modern promoters are so bent upon its being confirmed by the periodic law that the illustrious Berthelot, in his work Les origines de Z’AZcl&zie 1885 313 has simply mixed up the fundamental idea of the law of periodicity with the ideas of Prout the alchemists and Democritus about primary matter.” But the periodic law based as it is on the solid and wholesome ground of experimental research has been evolved independently of any conception as to the nature of the elements; it does not in the least originate in the idea of an unique matter; and it has no historical connection with that relic of the torments of classical thought acd therefore it affords no more indication of the unity of matter or of the compound character of our elements than the law of Avogadro, or the law of specific heats or even the coiiclusions of spectrum analysis.Kone of the advocates of an unique matter have ever tried to explain the law from the standpoint of ideas taken from u remote antiquity when it was found convenient to admit the existence of many gods-and of an unique matter.When we try to explain the origiii of the idea of an unique primary matter we easily trace that in the absence of inductions from experiment it derives its origin from the scientifically philo-sophical attenipt a t discovering some kind of unity in the immense diversity of i1idi.r-idualities which we see around. In classical times * He maiiitains (on p. 309) that the periodic law requiree two new analogous elements haring atomic weights of 48 and 64 occupying positions between sulphur and selenium although nothing of the kicd reaults from any of the different r e d -iiigs of the la{\ OF THE CHEMICAL ELEMENTS. 645 such a tendency could only be satisfied by conceptions about the immaterial world. As to the material w d d our ancestors were compelled to resort t o some hypothesis and they adopted the idea of unity in the formative material because they were not able t o evolvs the conception of any other possible unitg in order to connect t,he multifarious relations of matter.Responding to the same legitimate scientific tendency natural science has discovered throughout the universe a unity of plan a unity of forces and a unity of matter and the convincing conclusions of modern science compel everyone to admit these kinds of unity. But while we admit unity in many things we none the less must also explain the individuality and the apparent diversity which we caiinot fail to trace everywhere. It has been said of old “Give a fulcrum and it will become eRsy to displace the earth.” So also we must say “ Give anything that! is individualised and the apparent diversity will be easily understood ,” Otherwise how could unity result in a multitude ? After a long and painstaking research natural science has dis-covered the individualities of the chemical elements and therefore it is now capable not only of analysing b u t also of synthesising ; it can understand and grasp the general and unity as well as the individualised and the multitudinous.Unity and the general, like time and space like force and motion vary uniformly; the uniform admit of interpolations revealing every intermediate phase. But the multitudinous the individualised-like ourselves like the chemical elements like the membera of a peculiar periodic function of elements like Dalton’s multiple proportions-is characterised in another way we see in it-side by side with a connecting general principle-leaps breaks of continuity poiuts which escape from the analysis of the infinitely small-a complete abFence of intermediate links.Chemistry has foundan answer to the question as to the causes of multitudes ; and while retaining the conception of many elements all submitted to the discipline of a general law i t offers an escape from the Indian Nirvana-the absorption in the universal replacing it by the individua.lised. However the place for individuality is so limited by the all-grasping all-powerful universal that it is merely a fulcrum for the understanding of multitude in unity. Having touched upon tho metaphysical bases of the conception of an unique matter which is supposed to enter into the composition of all bodies I think i t necessary t o dwell upon anothev theory akin to the above conception,-the theory of the compound character of the elemerits now admitted by some,-and especially upon one par-ticular circumstance which being related to the periodic law is con-sidered to be an argument in favour oE that hypothesis 646 MENDELEEFF THE PERIODIC LAW Dr.Pelopidas in 1883 made a communication to the Russian Chemical and Physical Society on the periodicity of the hydrocarbon radicles pointing out the remarkable parallelism which was to be noticed in the change of pnperties of hydrwarbon radicles and elements when classed in groups. Professor Carnelley in 1886, developed a similar parallelism.The idea of M. Pelopidas will be easily understood if we consider the series of hydrocarbon radicles which contain say 6 atoms of carbon :-The first of these radicles like the elements of the 1st group combines with C1 OH and so 011 and gives the derivatives of hexyl alcohol, C,H,,(OH) ; but in proportion as the number of hydrogen atoms decreases the capacity of the radicles of combining with say the halogens increases. C6H1 already combines with 2 atoms of chlorine ; C6H, with 3 atoms and so on. The last members of the series comprise the radicles of acids; t.hus C6& which belongs to the VIth group gives like sulphur a bibasic acid C6H80,(OH), which is homologous with oxalic acid. The parallelism can be traced still further-because c6H5 appears as a monovalent radicle of benzene-and wit,h it begins a new series of aromatic derivatives so analogous to the derivatives of the fat series.Let me also mention another example from among those which have been given by M. Pelo-pidas. Starting from t,he alkaline radicle of monomethylammonium, N(CHa)Hs or NCH6 which presents many analogies with the alkaline metals of the 1st group he arrives by successively diminisliing the number of the atoms of hydrogen a t a seventh group which con-tains cyanogen CN which has long since been compared to the halogens of the VIIth group. The most important conseqnence which in my opinion can be drawn from the above comparison is t h a t the periodic law so apparent in the elements has a wider application than might appear a t first sight; it opens up a new vist,a of chemical evolutions.But while admitting the fullest parallelism between the periodicity of the elements and that of the compound radicles we must not forget that in the periods of the hjdrocnrbon radicles we have a dewease of mass a s we pass from the representatives of the first group to the next ; while in the periods of t h e elements the mass i,ncreases during the progression. It thus becomes evident that we cannot speak of an identity of periodicity in both cases unless we put aside the ideas of mass and attraction which are the real corner-stones of the whole of natural science and even enter into those very conceptions o OF THE CHEMICAL ELEMENTS. 6-17 Rimple bodies which came to light a full hundred years later than the immortal principles of Newton." From the foregoing as well as from the failures of so many attempts a t finding in experiment and speculation a proof of the compound character of the elements and of the existence of primordial matter it is evident in my opinion that this theory must be classed amongst mere utopias.But utopias can only be combatted by free-dom of opinion by experiment and by new utopias. In the republic of scientific theories freedom of opinions is guaranteed. It is precisely that freedom which permits me to crit,icise openly the widely diffused idea as t o the unity of matter in the elements. Experiments and attempts a t confirming that idea have been so numerous that it really would be instructive to have them all collected together if only to serve as a warning against the repetition of old failures.And now, as to new utopias which may be helpful in the struggle against the old ones I do not think it quite useless to mention a p h n t a s y of one of my students who imagined that the weight of bodies does not depend upon their mass but upon the character of the motion of their atoms. The atoms according to tliis new utopian may all be homogeneous or heterogeneous we know nol which ; we know them in motion only and that motion they maintain with the same per-sistence as the stellar bodies maintain theirs. The weights of atoms differ only in consequence of their various modes and quantity of motion; the heaviest atoms may be much simpler than the lighter ones; thus an atom of mercury may be simpler than an atom of hydrogen-the manner in which it moves causes it to be heavier.My interlocutor even suggested that the view which attributes the greater complexity to the lighter elements finds confirmation in the fact that the hydrocarbon radicles mentioned by Pelopidas while becoming lighter as they lose hydrogen change their properties periodically in the same mannei. as the elements change theirs according as the atoms grow heavier. The French proverb La critique est fucile mais l'art est dificile, however may well be reversed in the case of all such ideal views as it is much easier to formulate than to criticise them. Arising from the virgin soil of newly established facts the knowledge relating to the elements to their masses and to the periodic changes of their properties has given a motive for t h e formation of utopian hypotheses, probably because they could not be foreseen by the aid of any of the * It is noteworthy that the year in which Lavoisier was born (1743)-the author of the idea of elements and of the indestructibility of matter-is latei.by esa.ctlv one century than the year in which the author of the theory of graritatioii and mass was born (2613 N.S.). The affiliation of the idem of Lavoisier and those of Neatoii is beyond doubt, 648 MENDELkEFP THE PERIODIC; LAW various metaphysical systems and exist! like t tie idea of gravitation as a n independent outcome of natural science requiring the acknowledge-ment of general laws when these have been est>ablished with the same degree of persistency as is indispensable for the acceptance of a thoroughly established fact.Two centuries have elapsed since the theory of gravitation was enunciated and althougb we do not under-stand its cause we still must regard gravitation as a fundamental conception of natural philosophy it conception which has enabled as to perceive much more than the metaphysicians did or could with their seeming omniscience. A hundred years later the conception oE the elements arose; it made chemistry what it now is; and yet we have advanced as lit'tle in our comprehension of simple bodies since the times of Lavoisier and Dalton as we have in our understanding of gravitation. The periodic law of the elements is only 20 years old it is not surprising therefore that knowing nothing about the causes of gravitation and mass or about the nature of the elements we do not comprehend the rationale of the periodic law.It is only by collecting established laws that is by working at the acquirement of truth that we can hope gradually to lift the veil which conceals from us the causes of the mysteries of Nature and to discover their mutnal dependency. Like the telescope and the microscope laws founded on the basis of experiment are the instru-ments and means of enlarging our mental horizcn. I n the remaining part of my communication I shall endeavour to show and as briefly as possible in how far the periodic law contri-huteu to enlarge our range of vision. Before the promulgakion of this law the chemical elements were mere fragmentary incidental facts in Nature ; there was no special reason to expect the discovery of new elements and the new ones which were discovered from time to time appeared to be possessed of quite novel properties.The law of periodicity first enabled u s to perceive undiscovered elements a t a distance which formerly was inaccessible to chemical vision ; and long ere they were discovered new elements appeared before our eyes possessed of a number of well-defined propcrties. We now know three cases of elements whose existence and properties were foreseen by the instrumentality of the periodic law. J need but mention the brilliant discovery of gallium which proved to correspond to eka-duminium of the periodic law by Lecoq de Boisbaudran; of scan&iurn corresponding to eka-boron by Nilsori ; and of germanium, which proved to correspond in all respects to eka-siliciurn by Winckler.When in 1871 I described to the Russian Chemical Society the properties clearly defined by the periodic law whicb such elements ought to possess I never hoped that I shoiild lire t o uiention their discovery to the Chemical Society of Great Britain a O F THE CHEMICAL ELEJIEYTS. 649 a confirmation of the exactitude and the generality of the periodic law. Now that I have had the happiness of doing so I unhesitatingly say that although greatly enlarging our vision even now the periodic law needs further improvements in order that it may become a trust-worthy instrument in further discoveries.* I will venture to allude to some other matters which chemistry has discerned by means of its new instrument and which it could not have made out without a knowledge of the law of periodicity and I will confine myself to simple bodies and to oxides.Before the periodic law was formulated the atomic weights of the elements were purely empirical numbers so that the magnitude of the equivalent and the atomicity or the value in substitution possessed by an atom could only be tested by critically examining the methods of determination but never directly by considering the numerical values themselves ; in short we were compelled to move in the dark to submit to the facts instead of being masters of them. I need not recount the methods which permitted the periodic law a t last to master the facts relating to atomic weights and I would merely call to mind that it compelled us to modify tEe vnlencies of indium and cerium and to assign to their compounds a different molecular composition.Determinations of the specific heats of these two metals fully confirmed the change. The trivalency of yttrium which makes us now represent its oxide as Y,O instead of as YO was also foreseen (in 1870) by the periodic law and it now has become so probable that Cleve and all other subsequent investigators of the rare metals have not only adopted it but have also applied it without any new demonstration to bodies so imperfectly known as those of the cerite and gadolinite group especially since Hildebrand determined the speci6c heats of lanthanum and didymium and con-firmed the expectations suggested by the periodic law.But here, especially in the case of didymium we meet with a series of difficulties long since foreseen through the periodic law but only now becoming f I foresee some more new elementa but not with the same certitude as before. I shall give one example and yet I do not see it quite distinctly. In the series which contains Hg = 204 Pb = 206 and Bi= 208 we can guess the existence (at the place VI-11) of an element analogous to tellurium which we can describe as dvi-tellurium Dt having an atomic weight of 212 and the property of forming the oxide DtOa If this element really exists it ought in the free state to be an easily fusible crystalline aon-volatile metal of a grey colour having a density of about 9.3 capable of giving a dioxide DtO, equally endowed with feeble acid and basic properties.This dioxide must give on active oxidation an unstable higher oxide DtO, which should resemble in its properties Pb02 and Bi,O,. Dvi-tellu-rium hydride if it he found to exist will be a less stable compound than even H2Te. The compounds of dvi-tellurium will be easily reduced and it will form characteristic definite alloy5 with other metals. VOL. LV. 2 650 MENDELEEFF THE PERIODIC LAW evident and chiefly arising from the relative rarity and insufficient knowledge of the elements which usually accompanp didymium. Passing to the results obtained in the case of the rare elements beryllium scmdium and thorium it is found that these have many points of contact with periodic law. Although Avdeeff long since proposed the magnesia formula to represent beryllium oxide yet there was so much to be said in favour of the alumina formula, on account of the specific hcat of the metals and the isomorphism of the two oxides that it became generally adopted and seemed to be well established.The periodic law however as Brauner repeatedly insisted (Berichte 1878 872 ; 1881,53) was against the formula Be203 ; it required the magnesium formula BeO that is an atomic weight of 9, because there was no place in the system for an element like beryllium having an atomic weight of 13.5. This divergence of opinion lasted for years and I often heard that the question as to the atomic weight of beryllium threatened to disturb the generality of the periodic law or, a t any rate to requira some important modifications of it.Many Eorces were operating in the controversy regarding beryllium evi-dently because a much more important question was a t issue thau merely that involved in the discuflsion of the atomic weight of a rela-tively rare element; and during the coutroversy the periodic law became better understood and the mutoal relations of the elements became more apparent than ever before. It is most remarkable that the victory of the periodic law was won by the researches of the very observers who previously had discovered a number of facts in support of the trivalency of beryllium. Applying t8he higher law of Avogadro, Xilson and Petterson have finally shown that the density of the vapour of the berjllium chloride BeCl, obliges us to regard beryllium as bivalent in conformity with the periodic law.* I conside? the con-tirmation of AvdBeff’s and Rrauner’s view as important in the * Let me mention another proof of the bivalency of bwjllium which may have passed unnoticed as it was published in the Russian chemical literature.Hrving remarked (in 1884) that the density of such solutions of chlorides of metals MCl , :is contain 200 mols. of water (or a large and constant amount of water) regularly increases as the moleciilar weight of the dissolred salt increases I proposed to one of our young chemists M. Burdakoff that he should investigate the beryllium chloride. If its molecule be BeC1 its weight must be = 80 ; and in such a case it must be heavier than the molecule of KC1 = 745 and lighter than that of MgCl = 93.On the contrtlrj if beryllium chloride is a trichloride BCI = 120, its molecule must be heavier than that of CaC1 = 111 and lighter than that of E/3;nCI2 = 126. Experiment has shown the correctness of the former formula, the solution BeC1 i- 200H20 having (at 1s0/4O) a dencity of 1.0138 this being a higher density t,han that of the eolution KCl + 200H,O (= 1.0121) and lower than that of MgC1 + 200H,O (= 1.0203). The hivalency of beryllium was thue confinned in the caw both of the dissolved and the vaporised chloride OF THE OHE;MlCAL ELEMENTS. 65 1 history of the periodic law as tlie dimovery of scandium which iii Nilson’s hands confirmed tlie existence of the eka-boron. The circumstance that thorium proved to be qusdrivalent and Th = 232 in accordauce with the views of Chydenius and the re-quirements of the periodic law passed almost unnoticed and was accepted without opposition and yet both thorium and uranium are of great importance in the periodic system as they are its last members and have the highest atomic weights of all the highest elements.The alteration of the atomic weight of uranium from U = 120 into U = 240 attracted more attention the change having been made on account of the periodic law and for no other reason. Now that Roscoe Rnnimelsberg Zimmermann and several others have admitted the various claims of the periodic law in the case of uranium its high atomic weight is received without objection and it cndows that element with a special interest. While thub demonstrating the necessity of modifying the atomic weights of several insuficiently known elements the periodic law enabled us also to detect errors in the determination of the atomic weights of several elements whose valencies and true position among other elements were already well kuown.Three such cases are especially noteworthy those of tellurium titanium and platinum. Berzelius had determined the atomic weight of tellurium t o be 128, while the periodic law claimed for it an atomic weight below that of iodine which had been fixed by Stas at 126.5 and which was certainly not higher than 127. Brauner then undertook the investi-gation and he has shown that the true atomic weight of tellurium ie lower than that of iodine being near to 125. For titanium the exten-sive researches of Thorpe have confirmed the atomic weight of Ti =48 indicated by the law and already foreseen by Rose but con-tradicted by the analyses of Pierre and several other chemists.An equally brilliant confirmation of the expectations based on the peri-odic law has been given in the case of the series osmium iridium, platinum and gold. A t the time of the promulgation of the periodic law the determinations of Berzelius Rose and many others gave the following figures :-0s = 200; Ir = 197; Pt = 198; Au = 196. The expectations of the periodic lawX liave been confirmed first by new determinations of the atomic weight of pZatinunz (by Seubert, Oittmar and M’Arthur) which proved t o be near to 196 (taking 0 = 16 as proposed by Marignac Brauner and others) ; secondly, * I pointed them out in the Lielig’s Annalen Sup2lement Band viii 1871, 1’.211. 2 2 65% MESDELEEFF THE PERIODIC LAW by Seubert having proved that the atomic weight of osmium is really lower than that of platinum and that it is near to 191 ; and thirdly, by the investigations of Kruss and Thorpe and Laurie proving that the atouiic weight of gold exceeds that of platinurn and approximates to 197. The atomic weights which were thus found to require correc-tion were precisely those which the periodic law had indicated as affected with errors ; and it has been proved therefore that the peri-odic law affords a means of testing experimental results. If we succeed in discovering the exact character of the periodical relstionships behween the increments in atomic weights of allied elements discussed by Ridberg in 1885 and again by Bazaroff in 1887 we may expect that our instrument will give us the means of still more closely con-trolling the experimental data relating to atomic weights.Let me next call to mind that while disclosing the variation of chemical properties,* the periodic law has also enabled us to systemati-cally discuss many of the physical properties of elementary bodies, and to show that these properties are also subject to the law of periodicity. A t the Moscow Congress of Russian Naturalists in August 1869 I dwelt upon the relations which existed between density and the atomic weight of the elements. The following year Pyofessor Lothar Meyer in his well-known paper,? studied the same subject in more detail and thus contributed to spread information about the periodic law.Later on Carnelley Laurie L. Xleyer, Roberts-Austen and several others applied the periodic system to represent the order in the changes of the magnetic properties of the elements their melting points the heats of formation of their haloid compounds and even of such mechanical properties as the coefficient of elasticity the breaking stress &c. &c. These de-ductions which have received further support in the discovery of new elements endowed not only with chemical but even with physical properties which were foreseen by the law of periodicity are well known ; so I need not dwell upon the subject and may pass to the consideration of oxides.$ * Thus in the typical small period of Li Be,B C N O,F, we see a t once the progression from the alkaline metale to the acid non-metals such as are the halogens.t Liebig’s Annalen Erz. Bd. vii 1870. $ A distinct periodicity can also be discovered in the spectra of the elements. Thus the researches of Hartley Ciamician and others have disclosed fist the homoIogy of the spectra of analogous elements ; secondly that the alkaline metaIs have simpler spectra than the metals of the following groups ; and thirdly that there is a certain likeness between the complicated spectra of manganese and iron on the one hand and the no lesa complicated spectra of chlorine and bromine o OF THE CHENICAL ELEMEXTS. 653 I n indicating that the gradual increase of the power of elements of combining with oxygen is accompanied by a corresponding de-crease in their power of combining with hydrogen the periodic law has shown that there is a limit of oxidation just as there is a well-known limit to the capacity of elemenh for combining with hydrogen.A single atom of an element combines with at most four atoms of either hydrogen or oxygen and while CH and SiH repre-sent the highest hydrides so RuO and OsO are the highest oxides. We are thus led to recognise types of oxides just as we have had to recognise types of hydrides.* The periodic law has demonstrated that the maximum extent to which different non-metals enter into combination with oxygen is determined by the extent to which they combine with hydrogen m d that the sum of the number of equivalents of both must be eqnal t o 8.Thus chlorine which combines with 1 atom or 1 equiva-lent of hydrogen cannot fix more than 7 equivalents of oxygen, giving ClzOt while sulphur which fixes 2 equivalents of hydro-gen cannot combine with more than 6 equivalents or 3 atoms of oxygen. It thus becomes evident that we cannot recognise as a fundamental property of the elements the atomic valencies deduced from their hydrides ; and that we must modify to a certain extent, the theory of atomicity if we desire t o raise it to the dignity of a general principle capable of affording an insight into the constitution of all compound molecules. I n other words it is only to carbon, which is quadrivalent with regard both to oxygen and hydrogen that we can apply the theory of constant ralency and of bond by means of which so many still endeavour to explain the structure of compound molecules.But I should go too far if 1 ventured to explain in detail the conclusions which can be drawn from the above consideratiohs. Still I think it necessary to dwell upon one particular fact which must be explained from the point of view of the periodic law in order to clear the way to its extension in that particular direction. the other hand and their likeness corresponds to the degree of analogy between those elements which is indicated by the periodic law. * Formerly it was supposed that being a bivalent element oxygen can enter into any grouping of the atoms and there wm no limit foreseen as to extent to which it could further enter into combination. We could not explain why bivalent sulphur, which forms compounds such as could not also form oxides such as-while other elements as for instance chlorine form compounds such as-C1-0-0-0-0-K 654 JlESDkLEEFF THE PERIODIC LAW The higher oxides yielding salts the formation of which was fore-seen by the periodic system-for instance in the short series beginning with sodium-Na,O MgO A120, Si02 P205 SO, CI2O7, must be clearly distinguished from the higher degrees of oxidation which correspond to hydrogen peroxide and bear the true character of peroxides.Peroxides such as NhO, Ba02 and the like have long been known. Similar peroxides have also recently become known in the case of chromium sulphur titanium and many other elements, and I have sometimes heard it said that discoveries of this kind weaken the conclueions of the periodic law in so far as it concerns the oxides.I do not think so in the least and I may remark in the first place that all these peroxides are endowed with certain pro-perties-obviously common to all of them which distinguish them from the actual higher salt-forming oxides especially their easy decomposition by means of simple contact agencies ; their incapacity of forming salts of the common type; and their capacity of COIII-bining with other peroxides (like the faculty which hydrogen per-oxide possesses of combining with barium peroxide discovered by Schoene). Again we remark that some grbups are especially cha-racterised by their capacity of generating pcroxides. Such is for instance the case in the VIth group where we find the well-known peroxides of sulphur chromium and uranium ; so that further in-vestigation of peroxides will probably establish a new periodic func-tion foreshadowing that molybdenum and wolfram will assume peroxide forms with comparative readiness.To appreciate the constitution of such peroxides it is enough to notice that the peyoxide form of sulphur (so-called persulphuric acid) stands in the same relation to sulphuric acid as hydrogen peroxide stands to water :-H(OH) or H,O responds to (OH)(OH) or H,O,, H(HS04) or H,SO respondg to (HS04)(HSOJ) or H,S20,. Similar relations are seen everywhere and they correspond to the principle of substitutions which I long since endeavoured to represent as one of the chemical generalisations called into life by the periodic law.So also sulphuric acid if considered with reference to hydroxyl, and represented as follows-and so aIso-HO(SOzOH), has its correspondivg compound in dithionic acid-(SOzOH)(S020H) 01 H SZO6 OF THE CHEMICAL ELEMEYl’F. 65.5 Therefore also phosphoric acid HO(POH202) has in the same sense its corresponding compound i n the subphosphoric acid uf Saltzer :-(POH,O,) (POH ,02) or Hap206 ; and we must suppose that the peroxide componnd corresponding to phosphoric acid if i t be discovered will have the following struc-ture :-(H,PO,) or H4P208 = 2H20 + 2P03.* As far as is known at present the highest form of peroxides is met with in the peroxide of uranium UOa prepared by Fairley ;t while Os04 is the highest oxide giving salts.The line of argument which is inspired by the periodic law so far from being weakened bj the discovery of peroxides is thus actually strengthened and we must hope that a further exploration of the region under consideration will confirm the applicability to chemistry generally of the principles deduced from the periodic law. Permit me now to conclude my rapid sketch of the oxygen com-pounds by the observation that the periodic law is especially brought into evidence iu the case of the oxides which constitut.e the immense majority of bodies a t our disposal on the surface of the earth. The oxide8 are evidently subject to the law both as regards their chemical and their physical properties especially if we take into account the cases of polymerism which are so obvious when cornpal.-ing C02 with Si,O,,.I n order to prove this I give the densities s and the specific volumes v of the higher oxides of two short periods. To render comparison easier the oxides are all represented as of the form R20n. In the column headed A the differences are given between the volume of the oxygen compouud and that of the parent element divided by n that is by the number of atoms of oxygen in the compound :-$ * I n this sense oxalic acid (COOH)2 also corresponds to carbonic acitl, OH(UOOH) in the same way that dithionic acid corresponds to sulphuric acid, and subphosphoric acid to phosphoric ; therefore if a peroxide corresponding to carbonic acid be obtained it will have the structure of (HCO,), or H2C,06 = H,O + C,O,. t ‘lhe compounds of uranium prepared by Fairley seem to me especially instruc-tive in understanding the peroxides.By the action of hydrogen peroxide on uranium oxide UO, a peroxide of uranium uo44&o is obtained (U i= 2pO) it‘ the solution be acid; but if hydrogen peroxide act on urdnium oxide in the pre-sence of caustic soda a crjstalline deposit is obtained which has the comFosition Na4U0,4H2O and evidently is a combination of sodium peroxide NazO, with uranium peroxide U04. It) is possible that the former peroxide UO44H20 con-tains the elemelits of hydrogen peroxide and uranium peroxide U207 or even U(OH)BH302 like the peroxide of tin recently discovered by Spring which has the constitution Sn205H20,. f A thus represents the average increase of volume for each atom of oxygen con-So also lead must have a real peroxide Pb,O, 656 BURCH AND MARSH THE DISSOCIATION s.v. A. Nag0 2 . 6 24 -23 Mg,OZ . 3 . 6 22 - 3 A1,0 4 . 0 26 + 1 * 3 S i 0 4 . . . 2-65 45 5 . 2 P,O . 2.39 59 6 . 2 SzO6 . 1.96 82 8.7 s. I?. A KZO . 2 . 7 35 -55 Ca,O . 3.15 36 -7 sc,o, 3-86 35 0 Li,O,. 4 . 2 38 + 5 VgO . . . . . . . . 3-49 52 6 ‘7 Cr,O,. 2.74 73 9 . 5 I have nothing to add to these figures except that like relations appear in other periods as well. The above relations were precisely those which made it possible for me t o be certain that; the relative density of eka-silicon oxide would be about 4.7 ; germanium oxide, actually obtained by Winckler proved in fact to have the relative density 4.703. The foregoing account is far from being an exhaustive one of all that has already been discovered by means of the periodic law tele-scope in the boundless realms of chemical erolution. Still less is it an exhaustive account of all that may yet be seen but I trust that the little which I hare said will account for the philosophical interest attached in chemistry to this law. Although but a recent scientific generalisation it has already stood the tcst of laboratory verification and appears as an instrument of thought which has not yet been compelled to undergo modification ; but i t needs not only new applica-tions but also improvements further development and plenty of fresh energy. All this will surely come seeinq that such an assembly of men of science as the Chemical Society of Great Britain has ex-pressed the desire to have the history of the periodic law described in a lecture dedicated to the glorious name of Faraday

ISSN:0368-1645    

DOI:10.1039/CT8895500634

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

656 BURCH AND MARSH THE DISSOCIATION LXIV.-The Dissociation of Amine Vapours. By G. J. BURCH B.A. and J. E. MARSH B.A. University Laboratom, Oxford. THE theory of Van t’ Hoff that there is a definite relationship to Rpace of the four bonds or affinities of the carbon-atom has received such remarkable confirmation from facts that chemists have very natu-rnily attempted to extend the conception t o other elements especially tained in the higher salt-forming oxide. The acid oxides give as a rule a higher ralue of A while in the cuse of the strongly alkaline oxides its value is usually negative 170 facep. 656. (3) (4) 1.64 5 . 5 < 0.05 > 20 2.5 4.4 0'59 12 < 2 * U > 6 t 0 . 7 >20 DIAGRAM ILLUSTRATING THE; PER[ODIC VARIATION I N THE COMPOSITION OF THE HYDRIDES (OR METHIDES) AND OXIfiES OF THE ELEMENTS.(8) (9) (10) 0.917 19'6< -20 2.0 15 -9 ( 5 ) (6) (7) m = 1 H 1 l = t ~ 3.06 16.3 + 2 * 6 Be 9 -3 - - B 1 1 - - 3 1.8 39 10 3 - - N 14 1 - 3"- 5% Li lt 2 4 - - - c 1 2 - - - 4 >1*0 (88 (19 1.64 66 < 5 M. p. t. a. <1.0 > I 6 I 2 - 0 16 1 F 19 - -0.98 23 1 1 Na 23 It 1.7.4 14 2 - F g 24 - 2 t 2.6 11 I 3 - - A1 27 - - 3 2 . 3 12 1 4 - - -. si 28 - - 3 4 2 . 2 14 1 3 - - P 31 1 - 3% 4% 5" 2-07 15 2 - s 3 2 - 2 - 4" 5% 6" 1.3 27 1 c1 35; 1 - 3 - 5% - 7" 0.s7 45 K 39 li" 1 . 6 25 Ca 40 - 2i" (8.5) (18) sc 44 - - 3i" (5.1) (9 .4) Ti 48 - - 3 4 6.5 8.0 Cr 52 - 2 3 - - 6% 7 . 5 7 ' 3 Mn 55 - 2 t 3 4 -7 . 8 7.2 Fe 56 -8'6 6.8 CO 586 - 2t 3 4 8.7 6.8 N1 59 - 2.f 3 8.8 7'2 Cu 63 1.F 2 t 7 -1 9.2 2 - Zn 65 -.5.96 12 3-Ga 70 - -s.47 13 4 - - _.Ge 7 2 - 2 - 4 5 . 7 13 AS 7 5 - - 3 - 5" 4.8 16 2 - S e 7 9 - - - 4 - 6" 3.1 26 1 Br 80 1 - - -1 5 57 Rb 85 1.F 2.5 35 Sr 87 - 2-P 4 Zr 90 - - - 4 7 . 1 13 Nb 94 - - 3 - 5" 8.6 12 MO 96 - 2 3 4 - 6* 5 . 5 9'2 V 5 1 - 2 3 4 5 6% ?* 2+ 3 - - 6' 2-P 3 5" - 7" Y 89 - - 3.F (3.4) c;y 12.2 8.4 Ru103 - 2 3 4 - 6 -8 (1) 12.1 8.6 R h l 0 4 - 2 3 4 - 6 11.4 8 . 3 Pd 106 1+ 2 - 4 Ag 108 lt 10.5 10 8 6 13 7 . 4 14 3 - - 1 n 1 1 3 - 2 3 7 . 2 16 4 - - - Sn 118 - 2 - 4 6.7 18 3 - - Sb 120 - - 3 4 5 6 - 4 20 2 - Te 125 - - - 4 - 6% 4.9 26 1 I 127 1 -1-88 71 Cs 133 It 3.75 36 Ba 137 - 2.F 6.1 23 6.6 21 6.5 22 (6.9) (25) 10.4 18 19.1 9.6 2 - Cd 112 - 2.F 3 - 5% - 7% La 138 - - 3? Ce 140 - - 3 4 Di 142 - - 3 - 5 3 (14.) 5 (1) 4 - 6 (1) 29.5 8.5 ox 131 .- - 3 4 -32.4 8 - 6 R i g s - - - 3 4 - 6 21.5 9.2 Pt 196 - 2 - 4 19.3 10 AU 198 1 - 3 13.6 15 2 - Hg 200 li" 2? 11.8 17 3 - - TI 204 lt - 3 11.3 18 4 - - - Pb 206 - 2 t - 4 Yb 173 - -Ta 182 - - - -W 184 - - -.6 -8 5 9.8 21 3 - - Bi 208 - - 3 -4 (5) (1) 11.1 21 Th 232 - - -18.7 13 u 2 4 0 - - - 4 6 d. 2- RH,. RMe,. R. A. A i - - -- - -Na2O 2.6 24 -22 3.6 26 -3 Al2O 4.0 26 + 1 * 3 2.65 45 5.2 2.39 59 6.2 1 - 9 6 82 8.7 2.7 35 -55 3.15 36 -7 3.86 35 (0) 4.2 38 3-49 52 - - I ( + :).7 9-74 73 9 -5 - - -- - -- - - - - -Cu,O 5.9 24 9 -8 4.7 44 4.5 4.8 4.1 56 6-0 5.7 28 Gt-a3O,(5'I) (36) (4 *O - - -- - - - - -4.3 48 -11 5.7 43 -0.2 4 .7 5'1 +6'2 4.4 65 6 23 5-05 45 (-2) - - --_ - -__ - -Ag,O 7 - 5 31 11 8-15 31 2.5 h,03 7.18 38 2 *7 6.95 43 2.8 6 - 5 49 2 -6 5 . 1 68 4.7 - - -- - -5 . 1 60 -6.0 6 . 5 50 + 1 * 3 6.74 50 2 -0 9.18 43 (-2) - - -7 . 5 59 4 -6 6.9 67 8 - - -- - -A ~ ~ O ( 1 2 . 5 ) (33) (13) 11.1 39 4.5 8 . 9 53 4.2 T1203(9 '7) (47) (4 '3: - - -9.86 54 2 -0 (7.2) (80) (9) I-- --Beryllium . . Boron . ,. Carbon Nitrogen . . . Oxygen . . . . Fiuorine . . . Sodium . . . . , IEagnesium Aluminiuiii . . Silicon . . Phosphorus . . Sulphur . . . . Chloriiie . . . . , Potssuixm . . . Calciiim . . . Scaiitiiuin . . , Titanium ,. , Vanadium .C!iroriilttin . . , Mang,iricst . . , Iron * . Cobalt . Nickel. . . . Copper . . . . . Zinc Gallimn Germanium Arsenic . . . . . . Selenium . . . . Bromine. . . . Rubidium . . Strontiiun . . . Yttrium . . . . . Zirconium . . Niobium . . . . . . . Molyb!~cnuYn . (1) (2) Hydrogen < - 200' -Lithium . . . I 180 -(900) -(1300) -> (2500) --203 -< -200 -96 071 500 027 600 023 (1200) 008 44 128 114 067 -75 -58 054 (800) -(2500) -(2000) -(2000) -(1500) -1400 012 (1400) OK3 1350 017 10.54 029 433 -30 -900 -500 006 217 --7 -39 -(GO')) -(1500) -- -I -- -- - - -Ytterbium . . . Tantalum . . . Tungsten. . . . Rutlieiiiiirn . . Rhodi~ii~i . . . . Palladium .. Silvcr Cadmium . . . . Indiiim . . . . . . Till . -. Antimony . . . Tellurium. . . . Iodine . . . . . . Cesium . . , Barium . . . . Lanthanum . . Cerium . . . . . . Didymium . . . - -__ -(1500) -(2000) 010 (1900) 008 1500 012 850 019 320 031 176 046 230 023 432 012 4455 01'7 114 -27 -(600) -(700) -- -(800) -Thorium . . . Uranium - -(800) -Osmium . . . . . Iridium . . . . . Platinum . . . . Gold / . Mercury . . . . . TEidliuiii . . , Lead * . Bismuth . . . . . (2500) 007 m Go7 1775 005 10.15 014 -39 -294 031 326 029 268 014 10 11 12 ~~~ Tliroughont the table the values included in brackets are estimated values. The melting points of the elements are given in the first column (1) of numbers ; column (2) contains the mean coefficient of linear expansion between 0" and 100" of solid elements expreased in millionth parts e.g.in the case of bismuth the mean expansion of one metre f o r 1" is cc = 0.00014. In colamn (3) the relative densities of the ehncnts in thc solid or liquid state are indicated ; whilst column (4) contains the corresponding atomic volumes. Tlic number of hydrogen-atoms in the hydride or of methyl-groups in the methide is indicated in column ( 5 ) , tlie cornpsition of the methides being represented by small figures that of the hydrides by larger thick figures. The coniposition of the oxides referred to the type R,O, is shown in column (7). The * indic:ttes that the oxide is mnrlicdly acid the f- that it is markedly basic.Xniall figures denote comparatively unimpqrtant or less comnion oxitlcs and tliose which only exist in combination ; the large figures important and more common oxides known in a scpamte coiiclition. The fig-tlres in columns ( 8 ) (9) and (10) respectively denote the relative densitj of the higher salt-forming oxide its molecular volume and the '' volume " of an equivalent of oxygen in the oxide ; the negative values apply to those cases in which the volume of the oxide is less than that of the element contained in it. The number of the period is indicated in column (11). The number of missing elerrient,s is indicated by bracketed figures in the column of symbols thus between Didyrnium and Ytterbium 14 elements are wanting. Oxides such as CO and H,O, which do not directly form salts are excluded OF AMINE VAPOURS.657 those which enter into the composition of the so-called organic sub-stances. I n making this extension we are bound to keep in mind the principles of the original conception namely that the four valencies of the carbon-atom are directed to the four angles of EL tetrahedron of which the atom occupies the centre. I n this hypothesis as we understand it the equality of the valencies inter se is represented by the symmetry of direction and the equal length of the vectors from the centre to the four angles. The consistent development of such an hypothesis appears to u s to lead to difficulties of two kinds the first arising out of the geometrical conceptions involved in it and the second being met with in the attempt to extend it to othcr elements.T t ascribes a perfectly distinct existence to these four bonds so that in all carbon compounds we have to deal with neither more nor less than that number unless we make the additional assumption that in certain cases the carbon-atom may lose its tetrahedric character. And farther if the tetrahedr c relation of the valencies is unvary-ing it is difficult to conceive in what way the atom can be united by more than three of its bonds to one atom of any other element. We meet then with the difficultyof having to explain the existence of such compounds as carbonic oxide in which carbon ap.pears to be n3 longer quadrivalent or of certain cyanogen compounds as for example the isocyanides in which the carbon-atom is either com-bined by more than three bonds to a single nitrogen-atom or is bivalent R*N=C or R*N=C; so that in attempting t o re-move the one objection we are brought face to face with the other namely that ex hyporhesi we conceive the valency of each element to be constant.Such instances me rare in comparison with the number of bodies which fall in with the hypothesis of Van t’ Hoff but they are well known and well defined. We do not how-ever dwell f u r t h e r on this subject hoping to attack it experimentally later merely stating here that results we have obtained with the nitrogen-atom bear also on this matter. Willgerodt has brought forward the view that the nitrogen-atom may be regarded as having a configuration represented by a double tetrahedron.We have given some attention to the question of th 658 BURCB AND MARSH THE DISSOCIATION configuration of the atoms possible in the case of several elements and among them more particularly of nitrogen and we have come iudependeiltly to the same conclusion and have endeavoured to put the hypothesis to the test of experiment. Starting from the consideration that a nitrogen-atom combined with four or five different groups should give a compound capable of isomerism and that among these isomers there are two possible the form of one of which is the non-superposable image of the other w e have attempted to obtain such a body containing what is in fact an " asymmetric nitrogen," and capable one would suppose of rotating the plane of polarisation to the right or to the left.The separation of these isomers if they exist we have not yet succeeded i t 1 effecting. Attacking the problem from another point of view we find that a space configuration such as that given above requires that we consider nitrogen as essentially a quinquivalent o r pentad atom. We h a w tben to reconcile with this view the fact that nitrogen in a large number of cases appears to be triad. We have endeavoured to find an explanation in the supposition that one atom of nitrogen in its apparently triad condition may combine by its two available affinities with another similar atom to form a condensed molecule and that such molecules are readily dissociated by heat into the ordinary molecules containing quasi-triad nitrogen. To test the hypothesis we measured the expansion of a known quantity of amine vapours when the temperature was raised from that of the laboratory to loo" the pressure remaining constant.The apparatus used consisted of a horizontal tube AB about 700 mm. long and 2.5 mm. in the bore to which was attached the T-piece C of the shape shown in the figure. To A and C were titted rubber tubes with mercury bulbs F and G which could be raised or lowered as required. To the end D was attached the dis-tillation bulb E containing the substance to be experimented upon in the liquid state; and this again was connected with a Sprengel pump. The tube AR was enclosed in a glass jacket provided with two thermometers T and tubes S for the supply and exit of steam. The apparatus having been partially exhausted the mercury was caused to fill the tuhe AB completely by raising the reservoirs F and G.The clamp 011 P having been tightened G was lowered and raised repeatedly so as to ensure the expulsion of the air from the connections and the replacement of i t by the amine vapours. Then G having been lowered till the mercury stood just below the bend of the T-piece F was lowered so as to draw over some of the vapour into the tube AB. Then F was clamped and the Sprengel pump worked till the mcrciiry from G rose up the branch D OF AMINE VAPOURS. 65 9 When this waR done the clamp at D w w screwed tight and F lowered until the mercury from C reached a convenient fixed point, B in the horizontal tube within the steam jacket. Thus any possible condensation of the saturated vaponr wa% avoided the pressure on the enclosed gases being less than when they were drawn in.To make sure of this however the length V,, of the column of gas was finally increased by about 50 per cent. by himultaneously lowering F and Q. It may be noted here that con-densation was a t once evident on increasing the pressure after the gas was enclosed. Lastly the clamp on F was tightened and the volume of the gas taken by measuring the length V of the column enclosed in the horizontal tube the thermometers being read at the same time, Dnring the heating the mercury bulb F was lowered and the clamp slackened to permit thc gases to expand ; when the temperature was again steady the pres-siire was finally adjusted so as to bring the column a t B to exactly the same mark as before all the adjustments being performed with F so that neither the bulb C nor the clamp upon its tube was touched during the whole experiment.After measuring the volume V at this higher temperature as a further check upon the results the pressure in G was again lowered in some experiments and the mercury brought back by means of F to its original position at R, and the increased volume V3 once more taken. Lastly the steam was turned off the Spparst,ns allowed to cool, and a final measurement of the volume V at the temperature of the laboratory was made. Next steam was passed into the jacket 660 BURCH AKD MARSH THE DISSOCIATION It will be observed that the horizontal direction of the column of mercury at its upper extremity and the fixed position of the bulb G, enabled us to secure with great accuracy the same pressure for each pair of measurements.The smallness of the volume operated upon is however an objection which will be remedied in our next apparatus. Several blank experiments were first made with air to test the accuracy of the method and the average error was found not to exceed 0.5 per cent. in the expansion between 17" and 100". Then we introduced various amines into the bulb E and now obtained on heating an expansion of 5 01' 6 per cent. above the normal. Next we substituted ether vapour for the amines when the abnormal expansion to a great extent disappeared-though not com-pletely. This we ascribed to the difficulty of freeing the apparatus of the amines the scent of which hung about the rubber connections in spite of repeated exhaustions.Finally we operated on a solution of pure monethylamine in ether dried ovei. potash when the abnormal expansion re-appeared. The equivalence of VoPo to VIP at the temperature of the laboratory and of VzPz to V,P3 a t 100" proved that at each of these temperatures the vapour of the amines obeys Boyle's law ; while the equivalence of VIPl to V4P showed that the heating caused no permanent increase of volume. But a comparison of V1 Pz tl and V2 P2 tz showed that there was an increased expansion of the amine vapours which was not observed in the case of air or ether. The following are some of the results :-No. 1.-Test Experiment with Air. Pressure = 264 mm. Volume a t 13.5" Volume a t 100" V2 = 257.7 observed.V = 199.0 259.08 calculated. Here the error is about 6 per cent. No. 2.-Mixture of Mono- Di- and Tri-ethylatnine i n Aqueous Xotution. Pressure = 148 mm. Volume at 15" Volume at 100" V2 = 2340 observed. V = 159.0 205.9 calculated. This experiment gave an abnormal expansion of about 12 per cent OF AMINE VAPOURS. 661 No. 3.-The same as in No. x. Pressure = 383 mm. Volume a t 15". . Volume a t 100". V = 148.0 V = 207.25 observed. 19 1 * 68 calculated. Pressure lowered to 263 mm. Volume at 100" V = 300 V2P2 V3P3 = 78898 78900. The abnormal increase was about i'i per cent. but the prossure was not so low. No. 4.-The same M i x t w e of Amines dried over Potnsh. Pressure = 173.5 mm. Volume at 13.5" Volume a t 100" V = 167.0 observed.V = 221.0 157.5 calculated. On cooling volume a t 17 = 122 i.e. = 120.53 a t the origin:il Abnormal expansion of 6 per cent. with return to the temperature. original volume within the instrumental error. No. 5.-The same as No. 4. Pressure not noted but about 250 mm. Volume a t 16.5' V = 183.0 Volume a t 100" . V2 = 250.0 observed. 235.8 calculated. Abnormal expansion of 6 per cent. No. 7.-Monethylarnir~e in Aqueous Xolution. Pressure 598.5 mm. Volume at 17" V = 200 Volume at 100". . V2 = 272 observed. 257 calculated. Abnormal expansion of nearly 6 per cent. No. &-Test Experirned with Ether Vapour. Pressure = 385 mm. Volume a t 17" Volume a t 100" . V = 195.0 V = 253.5 observed. 250.4 calculated.Error about 1.2 per cent. ; but the mercury smelt of ethylamine GGZ BURCH AND MARSH THE DLSSOSIATION No. 9.-Test Experiment with Ether after Cowtinuom Exhaustion and Heating ofthe Tube. Pressure 697 mm. Volume at 15.0 Vo = 135 VOP = 94095 Pressure 452 mm. Volume at 15.5 V1 = 209 VIP = 94120 Pressure 452 mm. Volumeat 100*5,V2 = 2;s V2Pz = 125i55 Pressure 363 mm. Volume a t 100.5,V3 = 347 V,P = 1259Gl Observed volume at 100.5 = 278 Calculated 9 = 271 The error was larger than in the previous case; but after the experiment on coolirig down to 17" the observed volume was within 1 per cent. of the calculated and the mercury still smelt strongly of the amine. No. l@.-Monethylamine Dissoloed i n Ether dried over Potash. Pressure = 379.5 m u .Volume a t 17". . Volume at 100" V = 267.0 observed. V = 200.0 257.2 calculated. Pressure 291.5 mm. Volume at 100" V = 349.5 Volume a t 18". . Vb = 263.5 Relation of final volume a t 18" to original volume st 17" reduced The relations VoPo V,P at 15' and V2Pz V,P at 100" also varied The abnormal expansion was iu this case nearly 4 per cent. between to same temperature and pressure = 1 1013583. only by about 1 per cent. 17" and 100". The above experiments seem to show that to some extent a t least, t h e vapour of ethylamine breaks up when heated from 17" t o 1Odo into a larger nurnber of molecules. Similar abnormal expansion has been observed in bodies which must be regarded as completely satu-rdted in the single molecule-but in all these cases polymerisation i OF AMIINE VAPOURY.6ti3 structurally possible and we think that in the nitrogen compounds it is necessary if we are to extend Van t' Hoff's hypothesis to them. Wurtz wha investigated methylamine and ethylamine (Ann. Ch;m. Yhys. [Tj 30 467) was unable by ordinary means l o determine their vapour-density. Izarn to whom he referred the matter employing a new method, measured the vaponr-density of the two amines a t different temperatures and pressures and found in every case a greater value than that required by theory. Thus at 35.84' and 1128 mm., the density of ethylamine was 1.6027 observed as against 1.5568 calculated. Izarn however did not experiment at temperatures lower than 27" or higher than 56". Our own observations made a t pressures of from +th to +rJ of that employed by him in the experiment quoted by showing an abnormal expansion to take place on raising the temperature from 17" to loo" seem to indicate that the specific volume of the vapour is a function not so much of the pressure as of the temperature and it is on this that the hypothesis which we now put forward is founded.The equality of the four valencies of carbon which has been sufficiently established by experiment is well represented by tlJe symmetry of the tet,rahedron and we must suppose that 8 rise of temperature affects them all equallF. Carbon therefore unless in combiiiation with an element which is not symmetrical in its space relations must be tetrad a t d l temperatures. This property it can only have in common with those elements which can be represented by the five regular solids the valencies of which ex hypothesi must be 4 6 8 12 and 20 corresponding to the number of the bolid angles of those bodies.It is impossible therefore to find a geometrical representation for. diad triad atld pentad atoms which shall be symmetrical in three-dimensional space and i t becomes almost a iiecessary consequence of Van t' Hoff's hypothesis when we attempt to extend it to the nitrogen-group that we should have two of the \.aleucies different in value from the other three. Moreover this difference would be manifested above a certain critical temperature, but would probably disappear below it and further the union of an element of strong affinity with one of the valencies might render the other four equal with respect to atoms of weaker affinity.With regard to the latter supposition representing the pentad atom by a double tetmherli-on if we suppose one angle taken up for instance by chlorine the remaining four are symmetrically situated with respect to one point within the atom and may be saturated by f o u r equal atoms or groups as in the ammonium phosphonium and arsonium salts. The effect of certain elements in wenkeiiing the bonds of othe 664 THE DISSOCIATION OF AMINE VhPOURS. elements is a matter of ordinary observation (see Van t' Hoff '' La Chimie dans l'espace "). Compare for example the relative strength of the affinity between two carbon-atoms when combined with hydrogen oxygen or nitrogen e.g. CH3-CH3 ; CH3-COOH ; Again the action of heat in weakening chemical affinity is also a matter of common experience.Thus mercury cadmium and zinc in the gaseous state have no affinity in respect to atoms of the same kind whilst iodine vapour exhibits the same pheuomenon at high temperatures. Now as regards the nitrogen-atom i t appears that in contrast to carbon it is the hydrogen and hydrocarbon gronps which weaken the affinitty between nit,rogen-atoms. Thus we have N02-N02 but not NH4-NH4 nor NH3=NH3 a t ordinary temperatures. Hence in the case of the amines the bonds uniting the nitrogen-atoms in the double molecule will probably be extremely weak and likely to be destroyed even at a coniparatirely low temperature. It is interesting in this connection to recall the fact that Hofmann (Rer. 3 112) found that it was practically impossible to separate the three ethyl bases (mono- di- and tri-ethylamine) by distillation in spite of there being an interval of some 40" between the boiling points of ethjlamine and diethylamine as well as between those of diethylamine and triethylamine. Now it is conceivable that i n such a mixture a molecule of one amine may unite with ;t moleccle of a different amine to form a compound more stable than if both molecules were precisely similar and capable accordingly of being volatilised to a certain extent without being dissociated. In conclusion we would say that in our opinion the nitrogen-atom is essentially pentad and that when we find i t triad we have to deal with molecules which have been dissociated and in which the two available bonds of the nitrogen-atom are too feeble at the temperature Gf observation to enable two molecules to hold together. We hope to continue our experiments as to the valency and space configuration of the nitrogen-atom and other atoms. COOH-COOH; CH,-CN ; CN-CN

ISSN:0368-1645    

DOI:10.1039/CT8895500656

出版商:RSC    

年代:1889

数据来源: RSC

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665 LXV.-TThe Resin of Myoporum Platycarpum. By J. H. MAIDEX F.L.S. Curator of the Technological Museum, Sy diiey . A VERITABLE natural sealing-wax is yielded by a small tree which is found in the interior of Australia ; it occurs in the more arid portions of all the colonies except Queensland. The tree is JIyoporzcm platy-carpum R. Br. and it possesses a variety of local names such as ‘‘ Sandalwood,” “ Dogwood,” and “ Sugar tree ;” the latter because a manna exudes from it which is greedily sought after by the blacks, and is likewise much appreciated by colonists. It yields a resin, which is used by the aboriginals as a substitute for pitch and wax ; for example they use i t either alone or mixed with fat to cement the stone heads of their tomahawks to the fibre which joins them to the stick forming the handle.As has been already hinted it forms a natural sealing-wax and is sometimes used by people in the interior f o r this purpose. It would probably serve as a constituent of black sealing-wax ; alone it is too soft for keeping in this climate. It sometimes occurs in great quantities on the stem is hard and brittle brcaks with a glassy fracture which is a t first of a pu~ple o r indigo colour but becomes brown on keeping. Often it may be picked up from under the trees in rounded cir globular pieces. Two samples have come into the writer’s hands and a few notes concerning them will doubtless be interesting. The first from the Lachlan River New South Wales is in small rounded lumps usually weathered on the outside and having a pleasant empyreumatic odour ; these are of a dark reddish-brown colour fly with the slightest touch of the pestle and are easily powdered.The resin has a bright fracture which appears almost black b u t shows reddish-brown a t the edges. It softens even with the warmth of the hand and i f kept in a bott,le the heat of an average summer day is sufficient t o fuse pieces presenting fresh fractures. It presents some external resemblance to guaiacum resin (especi-ally when that substance conies to market in small lumps) but it is not so green in colour as the latter. It has no taste. Cold water has no effect on it but if the water be heated the resin melts and floats forming a liquid much resembling tar but of a purplish-brown colour. The water remains clear colourless and almost odourless.Light petroleum dissolves 46.8 per cent. of a reddish-brown resin, destitute of odour. Alcohol dissolves from the residue 28.1 per cent. VOL. LV. 3 666 HEYCOCK AND NEVILLE LOWERIXG OF THE E'REEZIXG of a deep reddish-brown resin which is almost black by reflected light, The residue was boiled in water and 1.7 per cent. of saline matter was extracted while '23.4 per cent. of accidental impurity was left behind. This is of a chocolate colour and under a lens was seen to consist of a little ligneous matter with a large percentage of in-organic impurity. It was quite free from gum. Summary. a-Resin soluble in light petrolenin . 46.8 P- 7 9 Saline matters 1.7 Accidental impu1.i ty . 23.4 100.0 , alcohol. 28.1 -The crude resin melts at 90.5". The second sample was procured from Netallie Wilcannia New South Wales. It presents no marked points of difference as regards physical appearance from the preceding one. On treating i t with alcobol the liquid is not so dnrk as that yielded by the preceding sample neither is the colour so rich. It resembles tawny port b u t is a little darker. Light petroleum extracts 48.6 per cent of resin and alcohol added to the residue extracts 36.4 per cent. In contains no tannic acid

ISSN:0368-1645    

DOI:10.1039/CT8895500665

出版商:RSC    

年代:1889

数据来源: RSC

摘要:

666 HEYCOCK AND NEVILLE LOWERIXG OF THE E’REEZIXG LXV1.-The Lowering of the Freezing Point of Sodium by the Addition of other Jletals. By C. T. HEYCOCK M.A. and F. H. NEVILLE M.A. IN a preliminary note communicated to the Society on March 21st, 1889 and published in the Proceedings No. 65 p. 41 we drew attention t o the lowering of the freezing point of tin produced by the addition of small quantities of other metals. Since then we have examined the behaviour of alloys of tin with sodium gold, bismuth and thallium arid have reexamined zinc through a long range. The accompanying table gives a summary of our results, using tin as a solvent POINT OF SODIUM BY ADDITION OF OTHER METALS. G G 7 TABLE I.-Fu71 produced in the Freezing Point of Tin by dissolving one Atomic Weight of Metal in 100 Atomic Weights of Tin (that is 11,800 parts).--Sodiiim . Aluminum Copper . Zinc . Silver. Cadmium . Gold . Tliallium. Lead . Bismuth Antimony . Mercury Melting . . points (Carnelley). -95 -6 700 .o 1054 -0 433 *o 954 so 320 .O 432 .O 1045 *O 39 *o 294 -0 326 *O 268 -0 Atomic weight. 23 27 63 65 108 112 1'20 197 200 203 208 210 Atomic fall. -2 -5 1 -34 2.47 2 -53 2 -67 2.16 rise 2 -3 2 -80 2 . 3 2 -6 2 . 6 2 -10 Different examples of A1 used. In a future communication we hope to give full details of these experiments and to show to what extent these atomic falls remain constant with increasing concentration. Sodium as a Solvent.Method of Experiment.-The crucible in which the solvent was melted except where otherwise stated consisted of a cylinder of cast iron 6-8 inches high and 5 inches diameter I n the axis of this cylinder a hole was bored from 1-2 inches diameter and about 4 inches deep. Within this hole an annular iron stirrer worked up and down by means of a small water motor-both the length of stroke of the stirrer and its rate of motion could be va~ied. The block rested on a double ring gas burner and its rate of cooling was controiled by the use of asbestos cloth wrappings and covers. The rate oE cooling was usually about a degree in two minutes. The thermometer made by Mr. Hicks of Hatton Garden was graduated i n an arbitrary scale of millimetres 10 mm. corresponding nearly with 1" C.As the readings were all made with a telescope, the temperatures could be read to nearly &th of a degree. The zero of this thermometer had been fixed by long annealing in oil according to the method Mr. Hicks adopts ; this precaution though not so necessary for low temperatures is indispensable for working a 668 HEYCOCK AND NEVILLE LOWERING OF THE FREEZING high temperatures. When tin is used as a solvent the zero of common thermometers changes during the course of a few hours. The bore of the thermometer was carefully calibrated and found to be slightly conical ; the correction due to this was plotted and has been applied to all the temperatures we give but we have accepted the fixed points sent with the thermometer so there may be a small 2 error which owing to the nature of the experiments is unim-portant.During the experiments the thermometer was clamped in the axis of the cylinder and raised about a millimetre from the bottom of the hole so that the stirrer worked round it along the whole length of the bulb. In making an experiment solid paraffin was first placed in the crucible and then a weighed quantity of sodium from 20-30 grams (in large sticks) was dropped in the molten paraffin forming a layerabout 0.5 inch thick above the sodium prevented loss by oxidation or splashing. The crucible was raised well above the melting point of sodium and allowed to cool slowly whilst constantly stirred. The thermometer was always observed t o fall steadily and then suddenly to rise through a short range of temperature from 1-2" C., i t then remained stationary for several seconds or even a minute.The highest temperature reached during this surfusion was taken to be the freezirig temperature of the metal or alloy; determined in this way the freezing points of most alloys are extremely constant. A t temperatures near its freezing point and even up to 250° sodium, unlike tin dissolves only a few metals; thus Au Li K Hg T1 and I n dissolve freely P b and Cd very sparingly whilst we have not suc-ceeded in dissolving at present appreciable quantities of other metals, such as Zn Sn Al Mg Ag Pt Fe. Tin even when fused with sodium fails to give a true solution. The method adopted for testing the solubility of metals was to fuse the sodium under paraffin in a test-tube and then to add small quantities of the metal iu fine division the temperature being raised to the boiling point of the paraffin.When cold a clean piece of the sodium was thrown into absolute alcohol when any dissolved metal separated out i n a fine powder generally in minute crystals. Efect of Gold on the Freezing Point of Sodium. Ignited precipitated gold dissolves very readily a t temperatures a few degrees above the melt'ing point of sodium. The freezing point after each addition of gold was determined twice the temperatures rarely showed a difference of a tenth of a millimetre POIST OF SODIUM BY ADDITION OF OTHER METALS. 669 TABLE IT,-Gold in Sodium. 1st Series. Expt. num- Wt.Na. - bere I (1). . . . (2) . . . . 26 '00 (3j . . (4) 0 .. . (5?. . . . (7) ( 8 ) . . . . (9) (10). . . . (6,. . . . (11). . . . (12). * * . (13). . . . (14) . . . . (15). . . . (1). . . . (2). . . . (3). . . . (4) . . . , 20 -425 7 7 7 7 7 Y Wts. of AU added in succes-sion. -0 *253G 0 -1895 0.2157 0 *3468 1 -1438 0 *8844 0.6522 1 *0145 0 -9388 1 -0352 1 -008 0 *9630 0 -261 0 *481 -2 -1 1 -316 3 -067 6 *483 Temps. of freez-ing point in 0" C. -97.47 96 *85 96 *51 96 *07 95.39 93 *09 91 -29 89 -96 87 -91 86 -07 83 *89 81 -92 82.1 83.0 82.1 2nd Series. 97.44 91 -99 88-59 82 -1 -Atoms of AU per 100 komsNa -0.1138 0 -1989 0 -2957 0.4519 0.9655 1.363 1 *6562 2 -1122 2 *5343 3 '0 3 -453 ----1 -2 I.* 953 3 *705 Atomic fall. -5 '45 4 *87 4 -74 4 '61 4 '536 4.535 4.535 4.525 4.5 4 *53 4 -518 -- --4 -51 4.53 4 *I4 Remarks. F. P. rather uncer-tain until a nucleus of solid alloy was used to determine solidifica-tion. Temperature remain ed etationary till whole alloy solidified. Raised to 155". Sodium being now more than saturated with gold additional sodiuni was added t o dilute the solution. (5). . . . (7). . . . (8) * * . . (9) . . . . (10) . . . (11). . . . (6). . . . 23 -565 25 *160 27 *205 29 -86 31 3'05 35 -015 39 *025 82 -99 a3 -99 85 *03 86 *14 86 -5 87 9 5 88 *75 3 -211 3 -022 2 -781 2 '534 2.390 2 -161 1 -94 4 -50 4 -45 4.46 4 -46 4 -43 4 '48 4-48 100 atomic weights of sodium will therefore keep in solution about 3.5 atomic weights of Au.Hence this represents the fully saturated solution of gold in sodium. The behaviour of a solution of gold in sodium appears t o be very like thati of a weak solution of sodiuln chloride in water (cf. Gutlirie Phil. Mag. [4] 46). 3 A 670 HEYCOCK AND NEVILLE LOWERING OF THE FREEZIYG The minimum temperature of 81.92" is singularly constant when reached remaining stationary until the whole mass has solidified. Pwperties of the Xodium Gold Alloys. When the alloys are treated with alcohol gold is precipitated in ve1.y fine needles. I n appearance the solid alloys resemble sodium, though slightly whiter in colour. They are somewhat harder to cut with a knife than ordinary sodium and the cut surfaces oxidise much more rapidly probably owing to the action on the moisture of the air of the couple formed by the gold and sodium.An alloy obtained by diluting with sodium the fully saturated sodium and gold alloy solution was analysed by adding weighed portions of the alloy to alcohol titrating with normal HCl for sodium, washing and weighing the gold. Two analyses gave a mean result-Found. Au 15-00 Na 85-03 100.03 -It appeared of interest to ascertain whether this alloy would remain homogeneous when kept fused for some time notwithstanding the enormous difference in the densities of gold and sodium. For this purpose a test-tube was filled with the alloy and kept at 130" for 48 hours under paraffin; it was then rapidly cooled and after solidification portions were cut off from each end of the cylinder (which was about 4 inches long) and analysed as before.Calculated from weights of Found. Na and Au used. Top of cylinder Na 85.33 85.75 7 7 7 Au 14.16 14.25 99-49 1oo.co 84.89 - -Middle of cylinder Na 7 7 9 Au 14.60 99.49 84.49 7 7 Au 14.60 99.49 -Bottom of cylinder Na -The defect in each case is due to traces of paraffin intermixed wit FALL I N THE FREEZING POINT OF SODIUM PRODUCED BY ADDING GOLD. C . T HEYCOCK AND F. H. NEVILLE ATOMS OF GOLD PER 100 ATOMS OF SODIUM. clvs.5- were ObtairzPd. hy soci?€Zum to sat. HARRISON & SONS LITH. ST MARTINS LANE. W.C POINT OF SODIUM BY ADDITION OF OTHER METALS.671 the alloy. It thus appears that when fused no separatiou of the metals takes place. The relative density of this alloy taken in naphtha was found to be 1.152 ; assuming t'he composition to be Na 85 per cent. Au 15 pel cent. and that no change of volume takes place on mixing the calcu-lated density is 1,141. Hence the density of the alloy is a mean of the densities of its components which perhaps indicates that the solid alloy is a mixture. This view is borne out by the comparatively large size of the crystals of gold which separate out when the alloy is treated with alcohol. As the full investigation of the physical and chemical properties of this alloy would have taken us away from our main subject we defer the repetition and further verification of these results for a future paper TABLE III.-!l'hallizm dissolved in Sodium.Expt. num-ber. I. ( 2 ) . . . . (3). . * . (4) (5). . . . (6) (8). . . . (7) (9) (10). . . . (ll) Wt. Na taken. 22 -53 7) 9 ) 9 ) 7 9 7 7 9 7 7 7 7 7 J 7 ) ) Wts. of ihallium added n succes-sion. -0 -327'7 0 -4865 0,3525 0 -3355 0.6515 0.6620 1 -8915 1 -561 1.280 1 *2015 Freezing point of solution. --97 -46 96 '81 95 '81 95 '04 94.34 93 *05 91 -65 87 -3 83 *64 80 -745 77 -87 Number ttoms T1 per 100 itoms Na. -0 -164 0 0408 0 -635 0 *753 1 -033 1-41 2 *36 3 '14 3 -783 4 *384 Atomic fall. --3 '93 4 'OM 3 -81 4 '143 4-269 4.120 4 *k28 4 -401 4 '683 4 '468 Remarks.Na raised to 180" be-fore adding this por-tion of T1. Raised to 150". Raised t o 14.5'. Thallium dissolves in sodium very readily as it is only necessary to raise the sodinm about '20" above its freezing point to clissolve rapidly a lump of thallium weighing a gram or so. The extent to which this lowering is continued has not yet been determined as we have not a t present a thermometer with a sufficiently open range. It is remarkable that thallium which is so nearly related to the alkalis on the one hand is readily soluble in sodium whilst lead the other element to which it is nearly equally closely allied is almost insoluble in sodium. When the mercury was added to the molten sodium a con-siderable evolution of heat and light took place.It is worthy o 672 HEYCOCK AND NEVILLE LOWERING OF THE FREEZING Expt. num-ber. -(1) . a . . (2) . . . . (3). . . . (4) . . . . (5) . . . . (7) . . . . (6) . . . (1). . . . (2) . . . . (3). . . . TABLE IV.-Mercury dissolved in #odium. Wt. Na taken. Wts. of Hg added in succession. 20 -13 9 9 9 9 -0.5605 0 -7410 0,5740 0 -5170 1.771 4 -950 -0 -5859 1 '4938 Freezing point of solution. -97 -47 96.6 95 -38 94 -46 93 -64 90 *93 ' 83.35 Number of atoms of Hg per 100 atoms Na. ---0 - 1986 0 -4609 0'6643 0 a 84'7 1.475 3 -228 Another Series. 97 -49 95.95 92 -25 -0 -335 1 -189 -Atomic fall. -4 '38 4 -534 4'531 4 -519 4-43 4 '374 -4.6 4 -4 Remarks.Raised to over 200' TABLE V.-Mixture of Thallium and Merczcry dissolved in Xodium. Expt. nuin-ber. -( l ) . . . . a (2) . (3) . (4) . . . a (5) . . . . . (6) . (7) * . . ~~~ Wt. of sodium added suc-cessively. -20 -13 + 2 '08 Hg 19 > 9 + 7 *53 (total Na 27.66). 9f > > 9 9 Wt. of thallium sdded suc-cessively. --1 *0425 1-163 -0.8205 1.27 1 el22 Freezing point of solution. -92 * 25' 89 -86 86 -97 90.10 88 *61 86 -29 84 -2 Number of atoms T1 per 1OC Na. -- -0 *585 1'237 0 '9006 1 *235 1 -795 2 -252 Total number of foreign atoms. Hg + TI. -----1 -765 2 -136 2 *66 3 -117 Atomic fall. --4 -4 due to Hg.4 -09 due to T1. 4 -27 due to T1. 4- 19 due to both T1 and Hg. 4 -16 due to both T1 and Hg. 4 '20 4 *26 due to both Hg and T1. note that the atomic falls do not indicate in any way the formation of a chemical compound as might be anticipated. Had the mercury after addition appropriated a portion of the solvent it should have made these atomic falls (?) increase as the number of atoms of solven POINT OF SODIUM BY ADDITION OF OTHER METALS. Gi3 diminished. It seems not unreasonable to suppose that a compound may be formed at first and dissociated afterwards through the great dilution of the solution. At present we have made scarcely any experiments with mixtures of three elements. To the solution of mercury in sodium Table IV (Experiment lo), thallium was added.TABLE VI.-Cadmium dissolved ilz Sodium. Expt. num -ber . (1) . ( 2 ) * . . . (3) . (4) . (5) . (6) . (7) . (8) . (9) . Wt. Na taken. 21 -07 J J Y J Y J 9 9 > Y J J J I Y J Wt. of cadmium added in uccession, -0 -0 0.0995 0 '102 0 0940 0 -1055 0 -0792 0 -078 0-106 0 -194 Freezing point of mixture. .-57 '49" 97 -11 96 -75 96 *43 96 *04 95 -83 95 -54 95'431 95 -43 Number of atoms if Cd per 00 atomr Na. -0 *0969 0 -1964 0.288 0 *3908 0 *468 1 0 -5441 0 *6475 0 *8365 Atomic fall. --3 -92 3 -74 3.72 3 -71 3 -55 3 '584 3 -173 -Remarks. Raised to 260". Raised t o 260". Raised to 240".Raised to 24Q0 be-fore deteimina-tion of freezing point . Raised to 260" be-fore determina-tion of freezing point. Cadmium dissolves but slowly in sodium and it is necessary to raise the temperature after each addition of cadmium very con-siderably. The table shows that the solution became fully saturated at the temperature of 95.43" when it contained 0.7642 gram of cadmium (total weight added experiments 2-8 inclusive) that is 3.05 per cent. cadmium. Beyond this further addition of cadmium ceases to produce any effect. The introduction of small masses of potassium is attended with almost unavoidable loss by oxidation. This was diminished as far as possible by cutting the potassium in a deep basin into which a brisk current of dry carbon dioxide was passed ; the potassium was then weighed in a tube full of carbon dioxide.We intend shortly to investigate further the action of potassium on aodium to see if th 674 HEYCOCK AND XEYILLE LC)WERIXG OF THE FREEZING Wt. Na Expt. number. taken* lowering holds good for considerable percentages of potassium, especially the behavionr of the liquid alloy. Number of Wt. of E Freezing atoms K successively. solution. 100 atoms addod point of added per Atomic fall. Na. TABLE V1I.-Potassium dissolved in Sodium, (1). . . . . . (2) . * . . . . (3) . * . . . . . (4) . . . . . . (5) . . . . . . . 34.83 0 -0 97 '4.9O - -> > 0 *1GO 9K -52 0 '2708 3 -58 ) J 0 -601 92 -88 1 -288 3 *58 2 ) 0 -744 88.81 2.547 3 *408 2 ) 0 *536 85 -93 3.455 3 -345 - 75 -9 0.0 97 *14 41 -87 - 97 *5 9 0,204 96 -53 0 -158 -3 ) 0 -1023 96 9 9 -Another -3.85 -3 *45 Silver in Sodium.Since silver even when finely precipitated (Stas' method) is practi-cally insoluble in sodium a t temperatures near its freezing point an attempt was ma,de t o dissolve the silver in mercury and then to add this amalgam to the sodium. The silver would probably under these circumstances be in a favourable condition for solution. 20.64 grams sodium freezing point 97-49" were taken and to this an amalgam of 0.201 gram of precipitated silver disolved in 2.16 grains mercury 'was added. Freezing point of mixture 92.2" and 92.11". Calculat.ing the effect produced by the mercury alone (from Table I V ) the lowering should have been 92-19.Hence we conclude that silver is insoluble in sodium and that tha amalgam behaved like a solution of a resin in alcohol when thrown into water, the silver being precipitated. Silver even when heated strongly in a test-tube with sodium did not dissolve. Zinc in Sodium. Zinc was treated in the same way that is by amalgamating with mercury but like the silver in the foregoing experiment it pro-duced no effect the fall being almost exactly accounted for by the action of the mercury alone POIKT OF SODIUM BY ADDITION O F OTHER XETALS. 675 Lithium in Sodium. Of all the metals lithium on account of its extremely low atomic weight presents the greatest interest. Unfortunately however it is exceedingly difficult to work wit,h in presence of sodium; even a t 100" it oxidises with great rapidity and attacks the iron blocks.Further on account of its very low specific gravity it is impossible to use more than a film of paraffin over the sodium otherwise the lithium floats and never comes in contact with the sodium. After the loss of a considerable portion of lithium these difficulties were partly overcome by placing a wide test-tube in the iron block and melting the sodium in it. Through the cork of the test-tube the shaft of a glass stirrer the thermometer and a small tube were passed. A trace of paraffin was addcd a good stream of nitrogen was then passed in and the sodium raised above the nielting point of lithium (180"). A weighed piece of lithium was then thrown in and rapidly stirred and the temperature reduced as quickly as possible.The preliminary experiments are omitted as worthless. TABLE V TIT.-Lithiunz dissolved in #odium. Lead in Xodiwn. Lead dissolves very sparingly indeed in sodium even when the Thus 31.6 grams of sodium f.p. 97*65" after addition of 0.1215 This gives atomic fall of Further addition of 0.1465 gram of lead produced no further temperature is raised considerably. gram of lead had a freezing point 97-59'. 4.6. fall in freezing point 676 LOWERING OF THE FREEZING POINT OF SODIUM ETC. Wts. of I n added in succession. ---0 *0303 0 *0576 0 9472 0 *2489 0 *1370 TABLE IX.-Indium in Sodium. Number of atoms of In per 100 atoms of Na. ---0 *0267 0 *0774 0 *2072 0 *4267 -Expt. number. (1) (2) (3) (4) (5) (6) ( 7 j . . (9) (10) . (11) (8) Wt. of Na taken. -23 -0 9 9 J J 9 9 J J Y 9 Freezing point of solution. 97 *6 97 *51 97.31 96 *32 96 *11 96 ‘09 Atomic fall. ---3 ‘37 3 -75 3 -765 3 -49 -To this saturated solution sodium was added. Wts. of Na added in succession. 3.88 1 -43 2 -00 3 *oo 4 -00 Total indium present. 0 *621 93 J J J 9 Y9 96.09 96 .I 96.14 96 ‘27 --0.4155 0 - 3783 0.3376 -3 -51 3 *51 3 -55 ~~~ ~ Indium dissolves easily in sodium. Potassium as a Solvent. Potassium has been used for a few metals only. The atomic falls are approximat,ely as follows :-Na 1.6 Au 1.8 T1 1.7. We intend to continue our researches and hope to be able soon to communicate the results to the Society. Xidney College Laboratory, Cambridge

ISSN:0368-1645    

DOI:10.1039/CT8895500666

出版商:RSC    

年代:1889

数据来源: RSC

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LXVIL-The Alloys of Lead Tin Zinc and Cadmium. By A. P. LAURIE. IN a former paper (‘ Trans.,’ 1888 p. 88) I have described the be-hariour of copper-zinc and copper-tin alloys in a voltaic cell and deduced from their behaviour that the metals combine with one mother forming respectively a compound of the formula Cu,Sn and Zn,Cu. The above metals are grouped together by Matthiessen as ini-parting to their alloys their physical properties in the proportion in which they are mixed one with another. It is therefore probable from this that they do not form compounds one with another but are merely mixtures. If this view be correct the electrometer should detect the more positive metal when the alloy is used in the voltaic cell in place of the zinc plate even though the quantity of the more positive metal present be very small.Un-fortunately there is very little difference in potential between lead tind tin and i t was necessary in consequence to use ten cells in series. The alloys were made of the best grain tin and of assay lead well mixed and cast in an iron mould in the form of thin plates. The cell used consisted of the plate of alloy a slightly acid solution of stannous chloride and a lead plate coated with lead chloride. The alloys made up contained (u) 1 per cent. of lead; ( b ) 10 per cent. lead ; ( c ) 50 per cent. lead ; and (a) 70 per cant. of lead. The E.M.F.’s obtained were as follows :-Pure tin 0.035 volt; ( a ) alloy 0.015 volt; ( b ) alloy 0.020 volt; (c) alloy 0.015 volt ; (d) alloy 0.015 volt. It will be seen from this table that whilst the introduction of 1 per cent.of lead modified the E.M.F. of the cell the introduction of more lead had no further effect and that there is therefore no evidence as far as the electrometer can show of the existence of a com-pound between lead and tin. While testing the E.M.F. of these alloys i t seemed of some interest to determine afresh the alloy of lowest melting point and study the distribution of lead and tin in blocks of alloys slowly cooled. To determine the lowest melting point some 800 grams of 50 per cent. alloy were allowed to cool and the mother-liquor poured off from thecrystds formed. This was done on two separate occasions, and the resulting alloy analysed the first having 60.2 per cent. of tin the second 60.4 per cent.of tin giving a mean of 60.3 per cent. The first alloys experimented on were the lead-tin alloys. VOL. LV. 3 678 LAURIE THE ALLOYS OF LEAD, of tin. This lowest melting point alloy is usually called in the text-books Sn,Pb which would give it a composition of 63.1 per cent. of tiii. It will be seen that its composition does not really agree with any definite formula although near enough to account for the assumption that it had one. (Tin has been taken as 118 in these calculations.) To determine the distribution of the metals on cool-ing a square block of bees-wax 1* inches in the side was bedded in a mass of plaster of paris and sand two holes being left to the outside ; the wax was then melted out and the alloy after thorough mixing, run in.Two holes one across the other up and down were then drilled through the blcck ; the tixrnings were collected as they came out and analysed. I n subsequent experiments the corners and centre of the block merely were analysed. Tlie results are given below. It will be seen that though some-what irregular in composition a general tendency is apparent for the tin to be thrown to the outside of the block. Only one alloy seems to be homogeneous namely that correspond-itrg to 21 per cent. of tin. This is the lowest point of the density curve a s given by other experimenters. Anal.ysis of borings in order through the block sideways 20.10 19.98 20.09 20.01 20.03, 20.06 20.04 per cent. From bottom to top of block 20.06 20.06, 20.04 per cent. (2.) Alloy made up for 50 per cent.of tin. Analysis of the corners gave for the top 51.9 50.21 49 4 50.5 per cent. of tin; for the bottom 50.33 50.03 50.7 per cent. of tin. Analysis of the centre gave 48.95 per cent. of tin. Analysis of borings through the sides gave in ordcr 63-72 63.37 59.1 61.16 62.4 63.6 per cent. Top corners 79.1, '79.95 80.2 80.2 per cent. of tin ; bottom corners 79.9 79.4 80.24, 80.3 per cent. of tin ; centre of block 73.2 per cent. of tin. As confirming the result obtained by the eledsometer I may mention that Spring in a recent. payer (BUZZ. Acad. Roy. BeZg. [ 3 ] , 11 86) states that he does not believe that these metals form a com-pound. The usefulness of these alloys for wiping a joint is owing to their behaviour on cooling one alloy apparently cry stallising out after another so that they remain in a pasty state for a considerable range of temperature.Matthiessen states that these metals do not even mix the lead retaining only 1.7 per cent. of zinc. Some alloys were therefore made up contain-ing 1 per cent. oiily of zinc cast in thin plates and tested on the (1.) Alloy made up for 21 per cent. of tin. (3.) Alloy made up for 64 per cent. of tin. Analysis from bottom to top 62.2 63.5 64.1 per cent. (4.) Alloy made up for 80 per cent. of tin. The next alloys examined were the lead-zinc alloys TIN ZINC AND CADXIUM. 679 electrometer ; the cell contained zinc chloride and lead plates coated with lead chloride. The plates gave a deflection of 0.483 volt (zinc = *496 volt) thus indicating the presence of the 1 per cent.of zinc. The plates were then scraped with a penknife and again tested. They now gave no deflecttion showing apparently that all or nearly all the zinc lay in the oiitside portions of the alloy. On analysing the inside portion it was found to contain only 0.4 per cent. of zinc. Some fresh alloy was made up cast in a circular form and a thin layer removed in the turning lathe. This coating containec! 2.4 per cent. of zinc showing that the lead tries to reject even tfhe 1 per cent. of zinc mixed with it. With reference to the failure of the electro-meter to detect the 0.4 per cent. i t may be pointed out that owing to local action a very minute trace of metal may be dissolved too quickly to show its presence; but this can always be remedied by amalgamating the plate.Lead t,hen apparently tries to reject every trace of zinc and any zinc found in it may be regarded as mechanically caught in the metal while co oliii g . The zinc-tin alloys were next tried i n a cell containing zinc chloride, stannotis chloride and tin. These metals seem to mix readily. The results are given below. The 1 per cent. alloy gave uncertain indications until amalgamated. Here again we have no indication of a compound. 1 per cent. zinc alloy after amalgamating, 0.530 volt. The intermediate alloys conf aining 10 50 and 70 per cent. of zinc gave similar deflections showing that a small qnantity of the more positive metal could he detected ; tlie metals therefore do not com bine. Alloys of lead and 3 per cent. cadmium and of tin and 3 per cent. cadmium were tested on the electrometer. The E.M.F. of cadmium alone was 0.322 volt that of the lead-cadmium was 0.264 and of the tin-cadmium 0.293 volt. Since then, 3 per cent. of cadmium can be detected in either tin or lead alloys of the metal we cannot suppose that cadmium combines with either of these metals. The results of these experiments then is to show that the electro-meter confirms the conclusions arrived at by Matthiessen namely that lead tin zinc and cadmium do not combine with each other when mixed topether. They also show the delicacy of the electrometer in detecting small quantities of more positive metals. Pure zinc 0.536 volt. Chenzical Lahorafo?y. People’s Palace. 3 B

ISSN:0368-1645    

DOI:10.1039/CT8895500677

出版商:RSC    

年代:1889

数据来源: RSC

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680 LXVIK-The Magnetic Rotatory Power of Nitrogen Compownds also of Hydrochloric Hydrobronzic and Hydriodic Acids and of some of the Salts of Ammonia and the Conzpound Amrnonias. By W. H. PERKIN Ph.D. F.R.S. IN the previous investigations of the magnetic rotatory power of substances in relation to their chemical composition which I have had the honour of laying before this Society my attention has chiefly been directed to compounds containing carbon hydrogen oxygen and the halogens. This inquiry has now been extended and in this com-munication an account is given of nitrogenous compounds. The object of this was to accumulate fresh facts so as to get more material for generalisation but rno1.e especially to study the influence of nitrogen upon the rotation of substances in which it exists in tri- and penta-valent conditions because it has been repeatedly shown that compounds containing carbon in an unsaturated state have a con-siderably greater rotatory power than those in which it is saturated, and it therefore was a matter of interest to see whether other elements exerted a similar influence.Substances of the following classes were examined in this inquiry : nitrates nitro-compounds nitrites cyanides ammonia compound ammonias and their salts. With reference to the last-mentioned compounds it was my original intention to examine the hydrochlorides or chlorides only but as these gave peculiar results it was considered desirable to include ammonium bromide and iodide and for further comparison ammo-nium nitrate and its sulphates; this made it necessary not only to determine the rotation of the salts themselves but also of the acids employed in their formation except sulphuric acid which had been previously studied.Before discussing any of the results which have been obtained it will be most convenient in the first place to give an account of the substances employed and their magnetic rotations. Nitric Acid. A quantity of nitric acid sp. gr. 1.52 was distilled with about 10 per cent. of H,SO (100 per cent.) the first part being rejected. It was then redistilled while a rapid current of carbonic anhydride was passed through it according to the directions given by Kolbe (Ann. Chem. Phys. 79 136) ; in this way a fraction WRS obtained which was very nearly colourless b. p.83.7-84.7' (corr.). Th MAGNETIC ROTATORY POWER OF NITROGEN COMPOUNDS. 681 t. 1 sp. rotation. composition of this acid was found to be 98.3 per cent. of HNO, or HNO -j- 0.060 mol. OH,. The density determinations gave-MoI. rotation. 15" 15" d- 1.5191 da 1-5390, d- 5" 1.5368 d$ 1.5043. 4" 4 5" 14' 13 13 12 12 Average 13 -According to Kolbe's table of densities this acid should have a density of 1.526 at 15". It is possible however that the two acids examined were not quite equally free from lower oxides of nitrogen, and this may account for this small discrepancy. The magnetic rotations gave-0 '52'74 1 -235 0 '5303 1'240 0 -5289 1'23'7 0 '5333 1 -246 0.5318 1 *243 0 -5303 1.240 ---I--I-- -Nitric Acid and Water. The dilute acid was redistilled before use nitrat.e of urea beiiig Its strength was 56 74 added to remove lower oxides of nitrogen.per cent. and its composition HNO + 2.67 mol. OH,. The density determinations gave-15" 15 d- 1.3571 25" 25" d- 1.3474. Kolbe's table gives 57 per cent. for a density of 1.358 at 15". The magnetic rotations gave 682 PERKIN THE MAGNETIC ROTATORY POWER t. 1 sp. rotation. Mol. rotation. I- I--21" 21 21 ATerage 21 0 -7987 3 *646 0 -8006 3 '655 0 '8031 3 *667 0 %008 3 *656 ----~~~~ Methyl Nitrate. This was prepared from methyl alcohol and nitric acid nitrate of urea being added to the mixture. It boiled constantly at 65" (corr.). The density determinations gave-12 -0" 13 -5 14 *O 14.5 5 . 0 5 *5 5 .8 6.0 Averago 9.5 --_ 15" 15 d-" 1.2167 5" 5 aa 1.2322, -d? 1'8241, IV" 2 * 050 2 -066 2 *058 2.052 2.065 2 -059 2 *054 2.057 2 *057 .-20" 80 d- 1-2096, d?" 1.2032. 2.5" Dumas and Peligot give 1.182 at 20" (A 15 26). The magnetic rotations gave-0 * 5852 0 * 5887 0 *5863 0 -5842 0.5951 0 * 5930 0 *5912 0 -5918 0 '5894 --Ethyl Nitrate. The specimen used boiled at 87.5437.7' (corr.). The densit'y determinations gave-4" d- 1.1305, 4" 10" d -" 1.1220, 10 15" 15" &- 1.1159, 20" 20" d- 1.1099 OF NITROGEN COMPOUKDS. Sp. rotation. 683 Mol. rotation. The magnetic rot,ations gave-t. 11 *oo 9 -8 9.5 10.6 10.0 9.5 9 '0 Average 9.9 o .a --Sp. rotation. 0 -6811 0.6847 0 -6862 0 -6873 0 -6864 0 *6846 0.6a3i o m 2 a Mol.rotation. 3 '073 3 '084 3 * 091 3.095 3 -080 3.093 3 -075 3 *08l 0.6845 1 3.084 Propyl Nitrate. This was prepared from propyl alcohol and nitric acid nitrate of After fractioning a few The boiling The urea being previously dissolved in the acid. times it was obt,ained boiling a t 110~2-110*7" (cow.). point given by Wallach and Schulze (B 14 421) is 110.5". density determinations gave-15" dlT 1.0631 5" 5 d 1.0747, 10" 10" d- 1.0688, 2 5" 23 d-> 1.0531. The magnetic rotations gave-d$ 1.0580, t. 10.0" 10 *o 10 -0 9-6 5.5 5.5 5 . 5 5.5 Average 7 . 7 - I--0 *7483 0 *7507 0 * 7483 0.7489 0 9536 0 -7499 0 -7539 0 '7519 0 a7507 -4.085 4 -097 4.083 4 *086 4 w93 4 -072 4 -085 4 -083 4.085 -Isobut yl Nitrate.This was fractioned a few times and the portion boiling betwe: 684 PERKIK THE MAGNETIC ROTATORY POWER 3 23.5-124.3" selected for exaniination. Its density determinatioiis gave-4" 4" a- 1,0334, 10" 10" a- i - o m , 25" 25" d- 1.0124. The magnetic rotations gave-t. 13 -5" 10.5 10.0 9.8 9 -6 9-8 9 . 7 9 *6 9 -5 6 -0 6 *O 5 . 6 5 . 6 Average 8.9 15" 15 20" 20" d- 1:0215, d- 1.0168, Sp rotation. 0 '8020 0.8012 0 -8035 0 '8049 0.8012 0 * 8070 0 -8049 0 -8055 0 '8056 0 *8116 0 -8093 0 '8057 0.8054 0 *8052 .--MoI. rotation. --5.184 5 *163 5.175 6 -184 5.158 5 -197 5 *183 5'186 5 -188 5.206 5 -190 5 -164 5.163 5 -180 -E t h y 1 ene Nitrate.Nitrog ly co I. This was prepared in the same way as nitroglycerin only using glycol instead of glycerin (p. 685). After being well wa.shed with water and then with a solution of sodium carbonate i t was obtained a3 a pale yellow oil. This was well dried over anhydrous potassium carbonate allowed to stand until clear and then decanted for use. This substance was first obtained by Henry (Rer. 3 529). As men-tioned by him i t detonates when struck on an anvil but not so easily as nitroglycerin. When heated in a test-tube it gives off a small quantity of red fumes boils and distils up the side of the tube ; if strongly heated it explodes with great violence. Nitroglycol is a somewhat thick clear pale yellow oil ; the colour is believed to be due to a small amount of impurity as i t disappears after some weeks.It requires several times its volume of alcohol €or solution. Aqueous potash has but little action on it in the cold, but decomposes i t on boiling producing a brown liquid. Cold alco-holic potash does not act rapidly upon this substance at first but th OF NITROGEN COMPOUNDS. 685 mixture gradually becomes warm and afterwards boils violently, becoming brown. The deiisity determinations gave-d- 15" 1.4960, 15 d? 1.5099, 4" 10" 10" d- 1.5012, 2 5" 25" d' 1.4860. The magnetic rotations gave-t. 13 -5" 13 -5 13.5 13 * 5 13 -5 10.6 1.1 * 5 11.5 12 *4 Average 12.6 20" 20" d- 1-4908, Sp.rotation. 0 '665'7 0 '6657 0.6654 0 '6664 0 6709 0 - 6697 0 -6700 0 *6700 0.6735 0.6686 Mol. rotation. 3 -753 3 -753 3 *752 3 -774 3'774 3 -767 3 -772 3 5'72 3 *795 3.768 -Nitroglycerin. To prepare this 60 C.C. of nitric acid density 1.42 freed from any red fumes by nitrake of urea were mixed with 100 C.C. of sulphuric acid and 20 C.C. of 45 per cent. fuming sulphuric acid ; t h i s mixture was cooled with ice and 80 C.C. of glycerin gradually added. After standing a few hours the product was poured into a large bulk of water the nitroglycerin collected and washed with water and then with a solution of sodium carbonate. A good deal of difficulty was experienced in getting the nitroglycerin sufficiently clear for ex-amination but it was accomplished eventually by heating i t to about 30° so as to render i t more fluid and placing it in contact with an-hydrous potassium carbonate.After keeping it at this temperature i t was allowed to cool and in about 24 hours it was warmed again and filtered through paper a vacuum pump being used. Finally a little phosphoric anhydride was shaken with it and after standing for some time it was decanted for use. I t s density determinations gave-15" 15" d- 1.6009 &" 1.6144 4" 10" 10" d-- 1.6066 20" 20" a- 1.5958, 25" 25 d- 1.5910 686 PERKIN THE MAGNETIC ROTATORY POWER The magnetic rotations gave-14 '0' 13 -0 12 * 5 12 -0 12'0 12 -0 14 '8 15 -5 16 *O Average 13'5 Sp. rotation. I --0 a 6865 0 -6860 0 *6857 0 * 6875 0 * 687'1 0 *6880 0.6848 0 %897 0 -6869 0,6870 1 Mol.rotation. 5 -404 5 *39B 5 -392 5 '404 5 -406 5 '408 5 *393 5 *428 5 *415 5 *405 -Isobutyl Nit.rite. This product was purified first by shaking with dry potassium car-bonate and fractionally distilling until the temperature rose to 77" ; the distillate was then again treated with potassium carbonate and re-fractioned a few times in a Wurtz flask with a very long neck. The product collected for examination boiled at 67-68'. T t was left with potassium carbonate for a short time and then decanted for use. The density determinations gave-4" d- 0.8878 4" 10" d- 0.8806, 10" 25" dg7 0.8652. The magnetic rotations gave-15" 15" d- 0.8752, t. 4.5" 4 .8 4 '8 5 ' 0 13.5 13 '0 12 '0 Average 8'2 Sp. rotation. 0 -8545 0 -8533 0 -8527 0.8521 0 * 8484 0 %428 0 -8475 0 * 8502 Mol. rotation. 5 '511 5.506 5 -502 5 -500 5 -537 5 '497 5 '521 5 -51 OF NITROGEN COMPOUNDS. 687 Nitromethane. This substance was dried with potassium carbonate. When dis-tilled it nearly all came over at 101" (cow.). The density determina-tions gave-15" 4" 4" 15" d- 1.1441 d- 1.1580, 10" 10" d- 1-1502, 25" 25 d 1.1330. The magnetic rotations gave-t. 1 sp. rotation. 9 -8" 9 -6 9 -6 9 . 6 10.7 10 -3 10 *o 9.5 0 -6289 0 -6289 0 -6282 0.6304 0 -6280 0 -6301 0 -6363 0 -6325 Average 9.9 I 0-6304 20' 20" d- 1.1382, Mol. rotation. 1 -853 1 ~ 8 5 2 1.853 1 -857 1 952 1.857 1 -875 1 %62 L- 858 Nitroe thane.The specimen used was dried with potassium carbonate. The density determinations gave-It boiled at 114-115" (corr.). 4" 4" d- 1.0685, 10" 10" d- 1.0615, 2'" 25 d A o 1-0461. 15" 15" d- 1.0561, g 1.0509, The magnetic rotations gave 688 PERKIN THE MAGNETIC ROTATORY POWER 12 *5" 11 - 5 10 -5 9 . 2 10 *5 9 -6 9 - 2 9 *o Average 10.2 --0 "7204 0.7207 0 9244 0 9257 0.7191 0 -7284 0 -7209 0 -7203 2 -835 2'833 2 *845 2 -848 2 *824 2 -858 2 %27 2 -824 2 '837 Nitropropane. This substance was prepared in the usual manner with silver nitrite and propyl iodide. These substances when mixed do not react quickly but after a very few minutes ebullition sets in with vigour, and the silver salt fuses apparently owing to the formation of a compound of the iodide and nitrite.It was therefore found better to add the nitrite t'o the iodide iu small quantities at a time and to get the reaction over before adding more ; in this way no fusible silver compound was formed. On distilling the product a mixture of nitrite of propyl nitropropane and propyl iodide was obtained. The nitrite was roughly fractioned off and the residual oil treated with successive portions of silver nitrite until perfectly free from propyl iodide ; it was then distilled and carefully fractioned a number of times. It boiled a t 130*5-131*5" (corr.) and was perfectly colour-less. The density determinations gave-4" 4 d 1.0221 15" 13" a- ~0108, 20" 20" d- 1.G062 a;: 1.0157, 25" 25 d- 1.0023.The magnetic rotations gave OF NITROGEN COMPOUNDS. 6 8!r t. 1 sp. rotation. 20 -0" 20 *o 18 5 18.5 18-5 18 - 5 18.5 20 *o 19 *o 19 *o 0 -7781 0 -7763 0 '7842 0 *7'791 0 -7763 0 '7801 0.7791 0 -7762 0 -7776 0 -7702 Mol. rotation. 3 -824 3 *814 3 -849 3 *823 3 -809 3 *a28 3 -823 3 -814 3 -827 3 *782 Chloropicrin. This substance was first dried with phosphoric anhydride and then It boiled constantly distilled from anhydrous potassium carbonate. at 112' (corr.). The density determinations gave-4" 4" d- 1.6855 15" 15 d 1.6670, 20" 20" d- 1.6594 10" 10 d- 1.6748, 25" 25" dL- 1.6528. The magnetic rotations gave-t.15 -6" 15.6 15.6 15 *6 15 *6 9 0 9 -0 9'0 9 *o Sp. rotation. 0 - 9800 0 *9804 0 * 9800 0 *9775 0 *9810 0 - 9905 0 -9887 0.9905 0 -9899 Average 12.7 1 0.9843 Mol. rotation. 5 -376 5 -378 5.376 5 '363 5 -382 5 -399 5 -399 5 *395 5'389 5 -384 Ammonia. a. Aqueous Solution. had the composition NHa + 2.10 mol. OH,. The product employed contained 31 per cent. of NH, and therefor 690 PERKIN THE MAGNETIC ROTATORY POWER 9" 9 9 9 9 Average 9 The density determinations gave-:;:I: 1 7.872 7 '858 0.9459 7 '920 0 -9417 7 -885 0 *9429 7 '895 0 * 9419 7 -888 ------4" 4" d- 0,8989, 1 so 15 d -o 0.8926. The magnetic rotations gave-10" 10" d- 0.8955, t. 9 '5" 9 - 5 9 .5 9 . 5 9 . 5 10 .o 9 *5 9 . 5 9 *5 ---Sp. rotation. 1 *1523 1.1491 1 *1489 1.1516 1 * 1499 1.1518 1-1527 1.1506 1 '14'73 --Mol. rotation. -3 *916 3.905 3 904 3 -313 3.908 3 *916 3 -917 3 *910 3 -899 -Average 9 . 5 I 1.1505 [ 3.910 Less OH2 2.10 mol. 2 *lo0 NH 1 -810 -b. Alcoholic 8olution. This was prepared with absolute alcohol that had been standing over anhydrous copper sulphate for months. It was then decanted and distilled. The solution contained 14.48 per cent. of NH3 and therefore had the composition NH + 2.18 rnol. C,H,O. It was saturated as far as would permit of its use with safety and began t o give off gas at about 15'. The density determinations gave-d40 0,7829, 4" The magnetic rotations gave-8" 8 d- 0.7794.t. I sp. rotation. Mol. rotation OF NITROGEN COMPOUNDS. 691 Ethy lamine. This and most of the other compound ammonias examined were obtained from Kahlbaum. The product used was kept over freshly fused caustic potash some days before distillation. When fractioned it mostly came over between 1'7.4 aud 18.4" and the specimen examined had this boiling point. The density determinations gave-4" 4" d- 0.7013, 15" 15 d- 0.6892. The magnetic rotations gave-t. 1 sp. rotation, 4 '5" 4.5 4.5 4.5 5 '0 5 . 0 5 *o 4 . 5 5 -0 6 -2 6 -4 5 -4 8 . 6 8 - 3 8 -6 9 -3 Average 5 . 8 -1 ,0068 1 -0048 1 *0103 1 r0106 1 *0106 1 -0130 1.0180 1 *0122 1 * 0098 1 *0125 1 *0140 1.0116 1 -0054 1 -0023 1 * 0067 1 a 0057 I 1.0097 ~ 10" 10" d- 0.6946, Mol.rotation. 3 -592 3 -585 3 -6@5 3.606 3 *608 3 %17 3 *631 3 * f i l l 3.605 3 -616 3 *623 3 %14 3 %10 3 -598 3 -615 3 -610 3.609 Diet hy 1 amine. This was carefully fractioned several times ; t h e bulk of the pro-duct then boiled at 56-57' (corr.) which appears to be about the true boiling point of this base. The density determinations gave-4" d- Oei226, 4" 10" 10" a- 0.7164, 15" 15 20" 20" cl -6 0,7116, d - 0.7070, 95O 0.7028. 2 (;<I2 PERKIN THE MAGSETIC ROTATORY POWER Sp. rotation, The magnetic rotations e v e -Mol. rotation. t. t. 1 sp. rotation. 5 -4" 6 '4 5 '4 5 - 4 13 *5 14 '0 14 -5 ~ ~ nfol.rotation. Average 9.1 1'1151 1 *1157 1-1169 1 '1 189 1-1203 1'1194 1'1192 1 '1233 1 *1186 ---- I I 1 -0095 1 '0054 1'0033 1 * 0060 G '9952 0 '9923 0 '9960 1 '0011 5 -682 5 '658 5 -647 5 *662 5 -662 5 *649 5.674 5 -662 --Trie t h y lamiwe. The specimen employed contained a little diethylamine; it was therefore fractioned several times from sodium which forms a com-pound with this base. The portion selected for examination boiled at 89-89.5" (corr.) mostly at 89". The density determinations gave-4" d- 0.7426 4" ,I 0" d- 0.7372, 10 25" dw 0.7257. The magnetic rotations gave-15" 15 20" 20" d 0*7:-531, a- 0.7294, 10.4" 10 -3 10 *3 10'3 10 '0 9 '8 9.6 9-3 Average 10.0 8 *496 8 -499 8 '508 8 '523 8'532 8 *522 8 -518 a 547 -,-8 '518 Propy lumine.The specimen examined boiled at 47.5-48.5" (corr.). The density dc t erminat ions gave OF NITROGEN COMPOUNDS. 15" 4" 4" 15 ti- 0.7222 a- 0.7330, t. 1 sp. rotation. 10" 10" d- 0.7268, Mol. rotation. 2 5" 25 d< 0.7149. The magnetic rotations gave-t. 6 * 5 O 5.5 5 . 0 5 -0 5 -0 15 -0 14 *5 Sp. rotation. 1 *0116 1 *0161 1 '0190 1.0176 1'0183 1,0134 1.0094 Average 9.6 I 1.0130 20" 20 0.7182, 693 Mol. rotation. 4 *540 4 *554 4 *563 4.557 4 -560 4.597 4.579 4 -568 4 '563 4 *564 Dipropyl amine. After being distilled two or three times most of the product was obtained boiling between 109.4" and 110.4".The density deter-minations gave-4" dQ 0-7524, 10" 10" d- 0.7471, 2 5" 25 d A o 0.7357. The magnetic rotations gave-15" 15 a L o 0.7430, 20" 20" d- 0.7393, I--- I --5 *8 5 .8 5 -8 6 -5 6 *5 15 ' 0 16 -2 16.8 17.5 Average 10.7 1 *0087 1'0051 1 '0101 1.0122 1.0101 1 -0000 0 *9975 0 *9960 0 *9968 1 -0041 7 '539 7 -512 7 -550 7 -571 7.556 7.553 7 -558 7 '553 7.547 7 *549 VOL. LV. 3 694 PERKIN THE MAGNETIC ROTATORY POWKR Sp. rotation. Tripyopy lamine. To obtain this dipropylamine alcohol and propyl iodide in equa volumes were heated in a sealed tube a t 100" for two or three hows. On cooling the product solidified to a crystalline mass. After dis-tilling with water to remove alcohol and propyl iodide potash was added and the volatile bases distilled off ; these when dried and frac-tioned gave tripropylamine boiling a t 155.5-156.5".This was agniri distilled after boiling with sodium for some time which att,acks any dipropylamine present. The boiling point however was not changed by this treatment. The iodide of tetrapropylammonium which was left after the removal of the volatile bases was distilled the mixture of propyl iodide and tripropylamine thus obtained treated with bydro-chloric acid &c. The tripropylamine obt,ained in this way boiled nt 155-157" but mostly a t lXO which is apparently the boiling point of this base. Romer gives it as 144-146" (Bey. 6 1101). The density determinations gave-Mol. rotation. d- 4" 0.7681, 4 10" 10" dL- 0.7634, 25" 25" d- 0.7539.The magnetic rotations gave-l so 15 20" 'LO d 0.7600, d- 0.7567, t. 10 *9 9 . 7 9 -0 9.2 10 *3 10.3 10 *3 10.3 Average 10.0 ---I--I--1 *ll67 1 *1238 1.1252 1 '1247 1.1205 1.1152 1'1208 1 *1194 1 * 1208 --11.631 11.691 11 *6'39 11 *696 11 '666 11.610 11.669 11 *654 11.664, -Isobut y lamine. The base employed boiled between about 67" and 74". On repeatedly fractioning the chief part was found to come over at 68-69" (corr.). Hughes and Romer (Ber. 7 511) give it as 65.5"; this is believed to be too lorn OF NITROGEN COMPOUKDS. Sp. rotation. 695 Mol. rotation. Its density determinations gave--4" 4 O d- 0.7464, 5.699 5.711 5 -69'7 5 -696 5 T O 1 5 -684 5 -694 5 -661 5 $84 5.692 --95" 25 Cr-" 0.7283.The magnetic rotations gave-15" 15 a -D 0,7363, t . 1 7 . 8 16.2 15 *O 15 '0 15'0 15 '5 14 *5 14 *5 14 - 5 Average 15.3 I-- -__-1 a 0320 1 -0355 1 *0344 1.0341 1 -0350 1.0313 1 -0343 1 -0284 1 *03Z8 1.0331 --Isobutylccminc and Water. Isobutylamine when mixed with water develops heat. The mix-ture examined consisted of equal vols. at 15" of each substance; the density of the mixture was for d- 0.9002 ; this shows that con-siderable condensation occurs on making this mixture the average density of equal vols. of isobutylamine and water being as follows :-15" 15" 15" 13 Isobutylamine d- 0.7362 Water. . . . . . . . . . 1 .OOOO Average density .0.8681 The molecular composition of this mixture is C,H,,N + 5*510H,. The magnetlie rotations gave-3 c 696 PERKIN THE MAGNETIC ROTATORY POWER 15" 15 15 15 15 -____ t. I sp. rotation. 1 ~ 0 1 . rotation. 1 -0460 11 -091 1 - 0484 11 *116 1 -0402 11 *030 1 *0431 11.060 1 - 0460 11.091 -- --Average 15 1 *0447 Isobutylarnine and Alcohol. These substances were mixed in equal volumes measured at 15". The composition of the mixture is represented by CIH,,N + 1.715 mol. CZHsO. The density determinations gave-11 -077 15" 15" d- 0.791. The average density of equal volumes of isobutylamine and alcohd at 15" is-Alcohol (spec. used) . . IsobutFlamine Average . . . . . . . . 0.7948 0.7357 0.7652 This shows that considerable contraction takes place on mixing these subs tames.The magnetic rotations gave-t . 15" 15 15 15 15 15 15 15 15 Averaee 15 Sp. rotation. 0 *9556 0 * 9541 0.9556 0 -9655 0.9587 0.9620 0 -9596 0 -9572 0 '95.48 0.9581 Mol. rotation. 10 *364 10 -348 10 -364 10 * 356 10.418 10 *348 10 a377 10.351 10 * 326 10 -361 D Less alcohol. . . . . . . a . . . . . . . . 4 *768 5.59 OF Nll'ROGEN COMPOUNDS. 697 Diisobutylamine. This product after several fractional distillations was obtained with a boiling point of 139-140" (corr,). Merz and Gasiorowski (Ber. 17 626) give it as 135-137". The original substance was very good very little high and low portions being separated by dis-ti I lation.The density determinations gave-10" 10 a; 0.7528, The magnetic rotations gave-20" 20" a- 0.7457, t. -16 *3O 15 -3 15 *O 15 -0 16 -0 15.5 15'0 14 *5 14 -5 14 -5 14 5 -Sp. rotation. 1 -0409 1 -0442 1 -0412 1 * 0385 1 '0373 1 '0334 1 -0382 1 -0373 1 -0378 1 -0349 1 -0401 ---1 ~ 0 1 . rotation. 9 *969 9 '992 9 -961 9 935 9 * 933 9 -891 9 *932 9 -918 9.924 9.895 9 '945 Arerage 15 *1 1 1 -0385 I 9.936 A1 1 y lamine. It was frac-tioned several times and the specimen selected boiled a t 53.2-53.4 (corr.). The boiling point given by Rinne is 58" (AnnuZen 168-262). The specimen used came over mostly a t 532-54'. When smelt it causes sneezing. The density determinations gave-4" 4 10" 10" a- om99, d- 0.7739, 'I 5" 15 'LO" '20" d- 0.7688, d- 0.7436, 25" 2 5 O d- 0.7583 698 PERKIN THE MAGNETIC ROTATORY POWER Rinne gives the density as 0.864 at 15".13" 13 13 13 13 Average 13 The magnetic rotations gave-1'1'71.9 1.488 1 -1697 7 *473 1'1731 7 -4.95 1 -1709 7 *4,81 1 -1768 '7.519 1.1725 7 '491 ----t. 1 sp. rotation. 13 *5O 13 .O 13 '0 13 *O 15 *5 15 *5 15 -5 15 *5 1 -3605 1 3642 1 - 3615 1 *3620 1,3320 1 '3508 1 '3545 1 -3548 Average 14.3 1.3575 Mol. rotation. 5 -593 5.609 5 -598 5 -599 5 -572 5.567 5 '583 5 '584 5.588 Pentarnethylenediumine NHz*CHz*CHz.CHz*CHz*CHz*NHz. The product examined was prepared by my son (W. H. P.). It boiled at 178-179" (corr.).Its density determinations gave-1.5" 15" d- 0.8855 4" 4" d- 0.8939, c u r - w UUJV. u- W 0 0 L . d . 10" 20" - ~-~ -25' a- U'8iYZ. 25 The magnetic rotations gave-As I had some quantity of this substnnce at my disposal and i t readily absorbs moisture it was carefully fractioned. The chief part of the product boiled at 178-180.5" (corr.) (a little of that which came over first and which probably contained a small quantity of water being collected separately). The density determinations gave OF NITROGEN COMPOUNDS. 15" 4 O 4" 15" d- 0.8846 d- 0.8930, 699 10" 10 d- 0.8881 20" 20" d- 0.8812, 25' 25 d 0.8i84. Ladenburgh gives its boiling point as 175-178" and its density 0" 4" a.t d ~- as 0.9174 (Ber. 18 2957). The magnetic rotations gave-t .-14 * 7" 14 -7 14 -7 14 *7 Average 14'7 Sp. rotation. 1 -1703 1 *1673 1.1713 1.1703 1 -1698 Mol. rotation. ~-7 -496 7.477 '7 *503 7 *496 7 *493 -___I This refractioned product therefore has given numbers for the molecular rotation practically identical with those obtained with the original product a small difference being observable in the specific rotation which is a little lower. The influence of this is neutralised by the slight change in the density. The average molecular rotation is 7.492. Piperidine. The specimen of this base used in the investigation boiled at 105*8-106*3 (corr.). The density determinations gave-15" 15 d-" 0.8664 4" 4" d- 0.8758, 10" 1 uo d- 0-8704, 25" 25 d-" 0.8591.c$$ 0.8626, The magnetic rotations gave 700 PERKIN THE MAGNETlC ROTATORY POWER 5.826 5 %Of3 5 -811 5 '803 5 *805 5 '821 5.893 5 *so7 _--- I---11 *o 11 '3 11 *3 11 '0 16 *O 14 -5 14 5 14.0 Average 13.0 1 *0714 1 -0676 1 -0684 1 *of570 1 '0641 1 *0686 1.0659 1 .OGC;ij 1 -0674 -Pip eridin e and Water . This base has a great attraction for water. The proportions used The density determinations gave- were molecular C5H,,N + OH,. 4" 4 d 0.9227 15" 15" d - 0.9133, 20" 10" 10" 20" 25" 25" d- 0,9097 d- 0.9173, d- 0.9063. The magnetic rotations gave-f. 16 '0 15 2 15 .3 14 -5 16 *O 16.0 Average 15.5 Sp. rotation. 1 '0724 1 -0709 1.0727 1.0783 1 * 0696 1 -0732 1 '0728 ---__I Mol.rotation. 6,724 6.711 6 "722 6 -753 6.707 6 "729 6 "724 1 *ooo 5 924 --P y ridin e. When kept with freshly-fused potassium hydrate it did not show any signs of containing water ; after several fractional distillations the principal part of the product was obtained boiling between 116.2-116.7" (corr,). The density determinations gave-The specimen used was obtained from Schuchardt OF NITROGEN COMPOUNDS. I-- -701 I--4" d- 0.9944, 4 10" d- 0.9894 10" 2 5" 25 d-Lo 0.9778. The magnetic rotations gave-15" 15" 20" LO" d- 0.9855, d7 0.9816, t. I sp. rotation. Mol. rotation. l o -5O 10 93 10 *8 10 -8 10 '8 14 -5 14 *3 13.0 Average 12.0 1 -9734 1 '9686 1 '9731 1 -9740 1 '9682 1 -9741 1 '9724 1 - 9723 1 *9720 --8.758 8 *738 8 *758 8 "762 8.736 8 -789 8 777 8.770 8 *761 --Propionitrile.This was well dried with anhydrous potassium carbonate and then carefully fractioned. The specimen examined boiled a t 98-98.2" (cow.). The density determinations gave-4" dq 0.7998, 15" 10" d- 0.7941, 25" 25 d- 0.7815. The magnetic rotations gave-t . 1 Sp. rotation. ---l o -5 10 -5 11 -0 11 * 5 1 2 '0 16 *O 36.3 16.7 --Average 13.06 0 8641 0 '8662 0 8668 0 -8624 0'8612 0.8624 0 *8588 0.8587 0 -8626 --10" 15 20" 20" d- 0.7896, d- 0.7853, Mol. rotation. --3.327 3 -335 3 '339 3 *324 3 '322 3'341 3 328 3'329 3 '331 -702 PERKIN THE MACINETIC ROTATORY POWER 10 *o 10 ' 5 11 -0 10 -5 10 -5 10.5 10 -5 Average 10.5 ,--Trimethy lene Cyanide.Obtained by digesting trimethylene bromide with cyanide of potas-The portion examined boiled at 285-287-4" Henry gives it as 274" (Bull. Chem. Sac. 43 618). The sium and alcohol. (cow.). density determinations gave-0 *9850 5 *152 0 -9841 5 *14Y 0.9856 5 *160 0 *9801 5.128 0 -9786 5 *120 0.9786 5 -120 0 -9793 5 -123 0.9816 I 5.136 - --4" d- 1.0031, 4 O 10" d- 0,9984, 10" 25" 25 d-o 0.9894. The magnetic rotations gave-d 15" 0.9952, 15 20 d7 20" 0.9922, sp. rotation. 1 MOL rot,ation. t. I Hydyochloric Acid. The strength of the acids examined was determined by titration, and also by precipitation. Solution I.-Saturated at about 20".It contained 41.70 per cent. of HC1; its composition was therefore HCL + 2.834 mol. OH,. The density determinations gave-4" 4" d- 1.2154 10" 10" d- 1.2113, 15" 15 d 4 1.2082. The magnetic rotations gave OF NITROGEN COMPOUNDS. 703 t. I Sp. rotation. Mol. rotation. I- ---16 '5" 16 -5 16 -5 16 -5 16 *5 19 -8 19 *7 Average 17.3 --1 '7130 1-7115 1 '7123 15'113 1.7112 1.7110 1 *7113 1-7117 - -6 * 882 6 -876 6 *863 6 *875 6 -887 6 %84 C; *885 6 *879 2 934 -Solution I.-This contained 36.5 per cent. of HCl. The density determinations gave-The corn-position was therefore HCl + 3.51 mol. OH,. 7 5" l 5 O d- 1.1866 d41 1.1939 4 2'" 'Lj0 d 2 1.1827. The magnetic rotations gave-t.11 -6" 11 *5 11 -5 11.5 11.5 10 *3 10.3 10 *3 10 -3 Sp. rotation. 1 G 7 5 1.6590 1 * 6581 1.6569 1'6557 1.6613 1 '6580 1 * 6599 1 -6580 Mol. rotat.ion. 7 -724 '7.731 7 -727 7 -721 7 *716 7 -737 7.728 7 '731 7 '722 Average 11.0 I 1.6583 I 7.725 3 -510 Less 3 -351 mol. OHz HC1 = . 4,215 Xolution 111.-This contained 30.86 per cent. of HC1; its composi-The density determinations gave-tion was therefore HCl + 4.543 mol. OH,. 15" 15" d- 1.1582 25" 25" d- 1.1548 704 PERKIN THE MAGKETIC ROTATORY POWER t. The magnetic rotations gave-Sp. rotation. Mol. rotation. 2 1 . 5 O 21 -5 21 *5 21 -5 21.5 --1.5559 8,841 1.5528 8 %26 1 -5577 8 *854 1 *5580 8 *856 1 * 5572 8 -852 -_--__ -SoZution IV.-This contained 25.6 per cent.of HC1; its comyosi-The density determinat'ions gave-tion was therefore HC1 + 5.893 mol. OH2. Average 21.5 1 1.5562 15" 15 d, 1.1288, 8 *846 The magnetic rot'ations gave-t . -21 '0 21 .o 21 '0 21 '0 20 '0 20 '0 20 .o 20 '0 20 *o Average 20.4 -25" 65 d- 1-1260. Sp. rotation. ~ - - -1 -4684 1 *4706 1 '4643 1.4669 1.4606 1 - 4643 1 e4.599 1 *4643 1 *4721 Mol. rotation. 10 '319 10 -334 10.290 10 * 306 10.261 10 -289 10 -257 10.288 10.343 1'4657 I 10.298 " Less OH2 5 *893 4.405 Solution V.-This contained 15.613 per cent of HCl ; its composition was therefore HCI + 10.856 12101. OH2. The density determilintioris gave-13- d- 1.0771, 15" 25" Zio d- 1.0745.The magnetic rotations p v e OF NITROGEN COMPOUNDS. 705 Sp. rotation. t* I Mol. rotation. I--I-- -1 -2'748 1 -2790 1 -2761 Average 16 I 1.2766 :r I 16 ----15 -254 15 *303 15 *268 15 *275 4 *419 20 * oo 19 *5 19 -5 1 9 . 5 19 *5 -.-Average 19.6 Hydrochloric Acid in Isoainyl Oxide. This contained 10.68 per cent. HC1; its composition wai HC1 + 1.932 mol. CloH2,0. The density determinations 1.0223 1 -0169 1 * 0223 1 *0178 1-0231 1.0205 --d? 0.8159 4" 4" 15" 25" 2 5" d- 0.8258, d- G.8132. The magnetic rotations gave-t. I sp. rotation. --- I Mol. rotation. 23.834 23 *693 23 *834 23 *715 23 %39 23 *783 21.572 2 a211 -The above solution was cloudy on account of the absorption of a small quantity of water and this rendered it difficult to read as the light was obstructed.A second solution was therefore prepared, great care being used to prevent the presence of moisture. It was obtained quite clear and contained 12-62 per cent. of hydrochloric acid the composition being HC1 + 1.570 mol. CloH2,0. Its density determinations gave-15" 15" d' 0-8221. 10" 10 The magnetic rotations gave-d- 0.8265 706 PERKlN THE NAQNETIC ROTATORY POWER t. 1 sp. rotation. Mol. rotation. I-I-- -14 14 14 14 14 -Average 14 1 '0338 19.754 1 *0382 19 '838 1 *0352 19. '782 1 0352 19 *782 1 '0382 19 '838 1 '0361 19 -799 --.-2 -265 Previous No. 2 a211 Average 2 '238 --t. --IJydrobromic Acid. This was prepared by acting on amorphous phosphorus with bromine in the presence of water ; the gas was freed from bromine vapour hy twice washing it with a saturated solution of hydrobromic acid holding amorphous phosphorus in suspension.Xohtion I fully saturated at about 20" contained 65.59 per cent,. of HBr; its composition was therefore HBr -+ 2.361 mol. OH,. The density determinations gave-4 O 4 d- 1.7978, 15" 13" The magnetic rotations gave-d- 1.7874. 16 * 5 O 16 .5 16 -5 16 -5 16 .5 19.5 19.5 Sp. rotation. 2 -6154 2.6134 2 *6123 2 6119 2 '6093 2 -6017 2 *6058 Average 1 7 . 4 I 2.6100 10" 10 d -" 1.7919, Mol. rotation. 10 '04'7 :O -039 10 *036 10.033 10.023 10 * 006 10 *022 10.030 I Less OH2 2 '361 7.669 -XoZution 11.-This contained 56 per cent.HBr ; i t s compositio OF NITROGEN COMPOUNDS. 707 t. 1 sp. rotation. was therefore HBr -!- 3.533 mol. OH,. gave-The density determinations Mol. rotation. 15" 15 d-o 1-6117, 22O 22 22 22 22 Average 22 The magnetic rotations gave-2 *3213 11 -597 2.3206 11 594 2,3202 11.591 2 - 3199 11 '590 2.3213 11 *597 2.3207 1 I *594 -____-, 25" % 5" d-- 1.6069. 8oZution 111.-This contained 39.71 per cent. HBr ; its composition The density determinations was therefore HBr + 6.831 mol. OH2. gave-4" 4" d- 1.3850, 25" 25 d- 1.3748. The magnetic rotations gave-1 5 " 15 d- 1.3i86, t. 1 sp. rotation. I-- -22 * 3 O 22 *3 21 *o 21 so 21 *o 22 0 20 *o 20 -0 20 *o 1 -8482 1 *8436 1 '8498 1 *8462 1 *8523 1 *a534 1.8510 1 -8539 1 * 8549 Mol.rotation. 15 -224 15 -186 15 -247 15.224 15 *273 15 -276 15.242 15 *266 15 275 Average 21.0 I 1.8503 1 15.246 Less OHz 6 *831 8.415 -_ -Solution IV.-This contained 24.6 per cent. of HBr ; its composition The density determinations was therefore HBr + 13.789 mol. OHz. gave 708 PElRKIN THE MAGNETIC ROTATORY POWER 18' 18 18 18 18 15" 15" d- 1*2049, 1 *4684 28.261 1 -4728 22 -367 1 4721 22 *356 1.4716 22 349 1 *4718 22.351 The magnetic rotatiom gave-16 *5 16 -5 16 *5 A-verage 16.5 3 5" 25" d- 1.2028. 1 '2687 33 -036 1 -2716 33 *112 1 *2731 33 -151 1 *2711 33 *099 -t. Average 18 I 1'4713 I 22.336 8.547 Lees OH .13 *789 -Solution V.-This contained 15.47 per cent. of HBr ; its composition The density determinations was therefore HBr + 24.580 mol. OH,. gave-i r o The magnetic rotations gave-25" 25" d- 1.1149. I I t. I sp. rotation. I ~ 0 1 . rotation. -I-- I-8.519 ~ ~~ - ~~ Hydriodic A cid. Solution I.-This coiitained 67.02 per cent. HI ; its composition was, This acid was freshly prepared therefore HI + 3.498 mol OH,. colourless and pure. The density determinations gave-15" 4!O d- 1.9600, 4" 15 20" 10" 20 10" d- 1.9489, d 1.9448 d- 1.9537, 1.9414. 2 OF NITROQEN COMPOUNDS. Sp. rotation. 709 Mol. rotation. The magnetic rotations gave-22.5" 22 *o 20 -0 20 *o Average 21'1 -t. 3 -9033 21 242 3 %974 21 *286 3 -8949 21 -248 3 * 9027 21.291 3 * 8996 21 -267 -.- -~ Solution 11.-This contained 65.1 per cent.H1; its Composition was therefore HI + 3.827 mol. OH,. The density determinations gave-4 O 4" 10" 10" a- 1.9182, a- 1.9118, 25" 25 d- 1.9003. 15" 15 20" 20" a L o 1.9073, d-- 1.9035, The magnetic rotations gave-t. 1 sp. rotation. 16.0" I 3.7713 16 -0 3'7833 17 *O 3 -7802 3 *7791 16 * 5 3 -7827 Mol. rotation. 21 -640 21 *709 21.712 21 -705 21 '710 21 $95 Average 16.5 I 3.7793 Less OH,. . 3 '827 17.868 SoZutiov 111.-This contained 61.97 per cent. HI ; its composition \ms therefore HI + 4.364 mol. OH,. The density determinations gave-4" d- 1.8349 4" 3 0" 10" a- 1.8280, 15" 15" 2 0" 20 d- 1,8244, d- 1.8220.VOL. r,v 710 PERKIX TEE MAGNETIC ROTATORY POWER The magnetic rotations gave-Sp. rotation. t. Mol. rotation. 18 *Oo 17 *5 17.5 17-5 17 *5 3 *5713 3.5768 3 *5713 3 * 5681 3 -5705 22 '4.83 22 *514 22 '479 22 -459 22 * 474 t. 22 '0° 21 .o 22 -0 22.0 21 0 21 *5 22 '0 22 '0 22 '0 21 '0 21 -5 Average 21 -5 3-5716 1 2 2 . 4 1 Sp. rotation. MoI. rotation. 3 '2108 23 '688 3-2166 23 * 723 3 *z169 23 -725 3 '2320 23 -764 3 -2134 23.700 3 '2171 23 -731 3'2137 23 *710 3 *2203 23 -759 3 -8220 23 764 3.2166 23 -723 3 2171 23 -731 3.2170 23 '721 -------___-Average 17.6 Less OH 4.364 Gblution IV.-Freshly distilled colourless and pure ; it contaiiied 56.78 per cent. HI ; its composition was therefore HI + 5.413 mol.OH,. The density determinations gave-4" 4" d- 1,7115 15" 15" a- 1.7091, 20" 20" d- 1.6988 10" 10" d- 1.7059, 25" 25 d- 1.6962. The magnetic rotations gave-18 *308 ~~ ~ SoZufion V.-This contained 42.7 per cent. ; its composition was, therefore HI + 9.342 mol. OH, OF NITRdGEN COMl'OUNDS. 15 -0" 14 '5 14 *5 14 '0 17 '0 16 -0 15.5 711 2 -4354 2 -436 7 2 *4350 2 *4340 2 *4326 2 -4385 2 -4327 ---The density determinations gaye-t . I sp. rotation. 10" 10 d- 1.4536, Mol. rotntiou. 1.5" do= 1.4507, 17 -Oo 15 -5 15 -5 15 - 5 ~-20" 20" 25" 25 d - - 1.4484, d- 1.4467. I -95444 33.763 1.9515 33 *702 1 *9500 33 G76 1.9544 33 -752 The magnetic rotations gave-~ p .rotation. 1 ~ 0 1 . rotation. 27 -958 27 -989 37 -947 27.930 27 -945 28 -003 27 '930 27 -94.5 9 -512 18 '403 Solution V1.-This contained 31-77 per cent. ; its compositiou was, The density determinations gave-therefore HI + 15.272 mol OH,. 15" 1 so d- 1.2977, The magnetic rotations gave-20" LO" dc- 1.2962. Solution VII-This contained 20.77 per cent. ; its composition was, The density determinations gave-therefore HI + 27.128 mol. OH,. 15" 15 d- 1.1770 25" 25" d - - - 1.1754. 3 D 712 PERKIN THE MAGSETIC ROTATORY POWER The magnetic rotations gave-t. 23 .03 2 1 . 0 2 0 . 5 20 *o 20 -0 20 0 19 -5 1 9 . 5 Average 20.4 Sp. rotation. 1 *5636 1 5673 1 *5644 1-56 14 1 -5649 1 *5640 1.5653 1 *5642 1 * 5650 Mol.rotation. 45.539 45 *631 45 *544 45 *540 45 *554 45.554 45 -562 45 523 45.556 Ammonium Chloride. The specimen of this salt used was recrpstitllised several times and then dried over sulphuric acid i n a vacnum. The solutioii used cont>iined 27.08 per cetit. of salt and therefore had the composition N H CI + SOH as neasly a s possible. This solution was a supematurnt,ed one and althongh its tendency to ct.yst,allise was very inconvenient, especially in determining the density it was thought better to piit up with that than w0i.l; with a weaker solution. The density determinations gave-15" 25" d- 1.0777. The magnetic rotations gave-t . 25 -0" 22 .o 22 .c 21 .o 20 0 20 .o 20 .o 20'0 Avetagc.21 -2 -20" 2uo d- 1.0783, Pp. rotation. 1.3851 1 . Y % l 1.38 1.6 1 3343 1 '3h3-2 1,3865 1.3850 1 38LO 1 3850 +-14.108 14 .lo8 14 *090 1s '081) 14.076 14.109 14 .C95 -- I 14.096 14'Og5 LCSS 8 mol. O H 2 . . 8 .OUO N€I,Cl = . 6'096 ~ OF NITROGEN COMPOUNDS. 713 t . 17.0" 17'0 16 *O 16.0 15 *8 15 * 8 15 .7 15 -7 Average 16.1 Attempts were made to determine the molecular weight of this substance by Raoult's process with acetic acid but it was fouiid to be insufficieiitly soluble in acetic acid. Sp. rotation. 1.5439 1.5401 1 '5393 1 -5401 1.5350 1'5381 1 *5401 1.54001 1 -5396 ------Eihylainine Hydrochloride. A nearly saturated solution of this salt was made and its strength found by determining the chlorine several times.It contained 60.58 per cent. of EtH2N,HCI and therefore had the compofiition EtH,N,HCl + 2.946 mol. OH2. The density determinations gave-loo 10 d- 1.0535, The magnetic rotations gave-20° %UO d- 1.0305. Mol. rotation. -10 -966 10 *939 10 -929 10.934 10 -910 10 * 934 10 934 i o w 9 10 -943 L&s 2.946 mol. OH2,. . . . . . . . 2 946 7 -997 A determination of the molecular weight of this substance by Raoult's process in glacial acetic acid gave 115.1. Theory requires 81*.i. This is high ; the solution however was rather strong 1.307 of salt in 100 of acid t h i s may have had a little to do with this result but probably dissociation was the chief cause. Diethylamine Hydrochloride.-4 very nearly saturated solution of this salt was prepared. Chlorine determinations showed that i t contained 61.58 per cent. The solution therefore had the composition Et,HN,HCl + 3-79 niol. 0 H,. 'The density determinations gave-10" 10" d- 1.0198 20" No d- 1,0164 714 PERKIN THE MAGNETIC ROTATORY PCWER 15" 15 15 15 15 15 The magnetic rotations gave-1.4113 13 *694 1 4125 13'705 1.4125 13.705 1 *4116 13.697 1 '4100 13,682 1 *4063 13 *646 I--- I -A determination of the inolecular weight of this salt by Raoult's This as The proportions used were process with acetic acid gave 139.9. in the case of the ethylamine salt is high. 1-072 of salt to 100 of acid. Theory requires 109.5. Solution of Diethyla.rfiine Hydrochloride in Absolute Alcohol.The salt used which was dried by fusion and heated until it boiled, was dissolved while hot in alcohol of 0.7947. The solution was very nearly saturated a t the ordinary temperature. The strength WRY known from the ainoniit of salt used arid afterwards checked by chlorine estimations. The solution contained 83-63 per cent. of salt, and had the composition (C2H5)2HN,HC1 t 8.138 mol. C2H,0. 15" 1 *5 The density determinations gave-15" 15 a-- 0.841 7, T71e magnetic rotations gave-t . --17 'Oo 17 '0 18 '0 18.0 18 '0 Sp. rotation. 1.0117 1 -0161 10132 I *0118 1 -0103 --25" 25" d- 0.8361. Nol. rotation. 32 *356 32 -497 32 -424 32 -376 32 -339 32 -298 Average 17 -6 1 1'0126 Less alcohol 2 '780 x 8 *138 .. 22 *624 9.674 -OF NITROGEN COMPOUNDS. 715 Triethylamine Hydr~cl~lo~ide. A nearly saturated solution of this compound was found to contain Its composition calculated from this 57.26 per cent. of the pure salt. is represented as Et,N,HCl + 5-75 mol. OH2. The density determinations gave-20" 20 d-i 1.0184 15" 15 d-0 1.0202, 25" 25" d- 1.0167. The magnetic rotations gave-t. 16" 16 16 16 16 16 16 16 Average 16 Sp. rotation. 1 -3285 1 *3317 1 *3328 1 *3351 1 *3319 1 -3326 1 *3331 1-3318 1 '3322 Mol. rotation. 17 -44.1 17'485 17 '498 17 -528 17 '487 17 -496 17 - 502 17 -473 17 -489 5 -750 11.739 -Tetrethylarnnzonium Chloride. The solution employed was somewhat supersaturated and deposited very large transparent crystals in cold weather.Chlorine determina-tions showed that it contained 55.62 per cent. of the salt; it would therefore have the composition Et,N,Cl + 7.333 mol. OH,. The density determinations gave-8" 8" d- 1.0358, 25" 25 d-" 1.0285. 15" 15" d- 1.0323, The magnetic rotations gave 716 PERKTN THE MAGNETIC ROTATORY POWER -~ 15 '3 15 '3 15 2 15.2 18 -0 18 '0 18 '0 Average 16 '6 18 -0 t. 1 sp. rotation. 1 -3069 1 -3084 1 '3094 1.3120 1 *3068 1 9068 1 *3072 1-3076 1 *3>'39 ---12.5 12 * 5 13 '0 13 '5 Mol. rotation. 1 *3436 1 3430 1 '3430 1-3113 20 * 926 20 -951 21 -016 21'008 20 -950 20 -902 20.950 20 955 Et4 ,C1 =. . 13 *624 Piperidine Hydro& loride.The strongest solution which could be conveniently used contained 52.7 per cent. of this hydrochloride and had the composition C5H,,N,HC1 + 6.055 mol. OH,. The density determinat>ions gave-4" 4" d- lg0716, The magnetic rotations gave-t. j sp. rotation. 15" 15" 1.0677, MoI. rotat.ioii. 16 -097 16 -090 16.097 16.080 16 -080 16 *089 --Average 13 *1 1 1'3424 Less OH 6 .055 C6HIlN,HC1 = 10 -034 Ammonium Bromide. Two solutions containing different quantities of this salt were The strength of the solutions was found by bromine examined. determinations OF NITROGEN COMPOUNDS. 717 20 *oo 20 -0 20 '0 20 *o Solution I.-This contained 40.423 per cent. of salt ; its composition The density determinations gave-was therefore NH,Br + 8.024 mol.OH2. 1 -5'291 18 -193 1 ?332 18 -233 1 .'i258 18-156 1 T232 18 *149 15" 15" 4" a- 1.3816 d- 2.2867 4 Sp. rotation. 25" 25" a- 1.2794. Mol. rotation. The magnetic rotations gave-t. I sp. rotation. I Mol. rotation. I 18'183 Average 20.0 I Less OH,. . 8.024 NH,Br = . 10.159 -Solution IL-This contained 25 per cent. of salt ; its composition The density determinations gave-was therefore NH4Br + 16.339 mol. OH,. 15" 15 d a 1.1586, The magnetic rotations gave-t. -22 *O" 22 *o 22 -0 16.5 16'5 16 -5 Average 19.2 -2 5" 2 5 O d- 11574. 1 -4135 1 -4162 1 *4147 1 *m45 1 *4075 1 . a 7 1 1 *4106 - --26 '594 26 -657 26 %Z9 26 *406 26 *462 26 -454 26 -535 --v Less OH2 .16.339 -10 *19 718 PERKIN THE MAGNETIC ROTATORY POWER t. Amnboitium Iodide. ~ Sp. rotation. Mol. rotation. This salt was purified by recrystallisution from alcohol and in this way was obtained quite white. It was dried in a vacuum. The strength of the solution used was found from iodine determinations, made by precipitation with silver nitrate. I n the first preparation the solution was filtered through paper but it was found that this caused it to turn brown very rapidly mid made the readings of the magnetic rotations very difficult. It is much better therefore not t o filter the solution but to decant it if necessary. SoZution I.-This contained 60.44 per cent. salt = NHJ + 5.273 mol. OH,. The density determinations gave-3 -0124 3 -0115 3 -0145 3 *0176 4" 4" a- 1.6021, 25 -193 25 *191 25 -217 25 -235 2 5" 25" d- 1.9525.The magnetic rotations gave-15" 15" d- 1.5961, 20 *5" 21 -5 21 5 21 -5 Average 21.2 Less OH2 ,. 3.0140 I 25.209 5.273 ~ NHII = 19.936 Solution 11-This contained 58.46 per cent. of ammonium iodide ; The density determinations gave-its composition was therefore NHIT + 5.722 mol. OH,. 10" 10" d- 1.5727, 25" d-25" 15" 15" d- 1.5701, 1.5665. The magnetic rotations gave OF NITROGES COMPOUNDS. 719 20 '0° 20 '0 20 .o 20 '0 20 '0 20 '0 20 -0 Average 20.0 t. 1 sp. rotation. 2 -7332 26 -872 2 -7917 26 *657 2 -7332 26 *67l 2 '7333 26 -686 2 -7264 26 *621 2 -733 a 21; -674 2 -7274 26 -615 2 -7312 26 *656 __---MoI.rotation. 14.5O 14-5 15-0 15 -0 20 '0 18 -0 2.9277 2 -9340 2 -9415 2 *9475 2 -9331 2 -9301 25 *688 25 -743 25 -812 25 -804 25 -747 25 -738 -Average 16.1 I 2.9356 I 25.754 Less OH,. . 6 -722 --NHJ = . 20-032 Solution IIL-This contained S4.64 of salt ; its composition was, The density determinations gave-therefore,NHJ + 6.685 mol. OH,. 15" 15" d- 1-3122, The magnetic rotations gave-t. 1 sp. rotation. Mol. rotation. NH41 = . 19 -971 Solution IT.-This contained 30.5 per cent. of salt ; its composition The density determinations gave-was therefore NHJ + 18.333 mol. OHz. 13" 15" d- 1.2351 25" 25 d-" 1.2334. The magnetic rotations gave 720 PERKIN THE MAGNETIC ROTATORY POWER t. 21 -0 21 -0 22 .o 21 *5 22 '0 I Sp.rotat,ion. Mol. rotation. 1 -7949 38 -44% 1 -7977 38 *465 1 -7896 38.323 1 -7909 38.394 1 -7905 38.323 ,----Average 21 *5 I 1.7927 I 38.382 Less OH2 . 18.333 17 * oo 16 .O 16 .O 15 '0 15 '0 ~ 20.049 1 -2790 51 -561 1 -2848 51 .762 1 '2834 51 -702 1 *2848 51 *730 1 * 2863 51 *788 Results of the Four Solutions. Solution I. 60.44 per cent . 19.936 ?9 11. 58.46 , 20.032 , 111. 54-64 , . . . . . 19.971 , IV. 30.5 , 20.049 Average 19.997 Solution of Ammonium Iodide in Absolute Alcohol. The iodide of ammonium was well dried at loo" and then boiled and kept with absolute alcohol some days ; this was poured off and the salt twice more boiled with fresh quantities of absolute alcohol.the third solution being kept for use. The alcohol used had a density 15" 15" of d- 0.7947". The strength of the solution was found by iodine determinations; it contained 21.10 per cent. of salt and had the composition NHJ + 11.782 mol. C2H60. The density determinations gave-10" 10 Lzpo 0.9460, The magnetic rotations pve-d15" 0.9421. 15" t. I sp. rotation. 1 Mol. rotation. Average 15.8 I 1.2836 1 51.709 32 *754 18 -955 Less alcohol 2 5'80 x 11 -782 OF NITROGEN COMPOUNDS. 721 t. 1 sp. rotation. Ammorbiu rrL Nitrate. The aqueous solution used contained 59.7 per cent. of this salt; The density determinations gave-its composition was therefore NH,NO + $OH2. Mol. rotation. 6" 6 d- 1.2864, Sp. rotation. 95" 25 d+ 1.27764. Mol.rotation. The magnetic rotations gave-1 .oooo 1.0061 0 *9956 1.0061 1 *oooo 1 -0016 15" 15" d- 1.2814, 6 *847 6 %56 6-615 6.664 6 -658 6 $48 -_I--I -- I- -16 *O 16.0 16 -0 16 '0 15.0 15 .O 0 -9147 0 -9191 0 -9172 0 -9 176 0 -9127 0 -9130 5.315 5 *341 5 *329 5 -332 5 '302 5 -304 ----Average 15.6 1 0.9157 1 5'320 3 .OOO Less 30Hz . . . . . . . . . . . . . . . 2 '320 Acid Xulpphnte of Am,moniwn. The solution of this salt used was slightly supersaturated ; it con-tained 66.67 per cent. of salt, and had the composition NH,HSOJ + 3. I 93 mol. OH,. The density determinations gave-d- 15" 1.4429, 15 The magnetic rotations gave-t. 18.0 17 '0 17 '0 15 '0 1 5 . 0 25" 25 d 1.4387.Average 16.4 Led8 OH2 . . . . . . . . . . . . . . NH4HS04 = 3 '193 3 *455 - . . . . . . . . . . . . . . . 722 PERKJK THE MAGNETIC ROTATORY POWER Amnaonium Xulphate. An aqueous solution containing 40.00 per cent. of this salt was used ; The density determinations gave-its composition was therefore (NH4),SOp + llO&. 10" 10" d- 1.2308, 20" 20" d- 1.2285. The magnetic rotations gave-t. 16 '0 14 *5 11 *5 10 *5 23 -0 23 -0 23 *O 23 *O 18 *O Sp. rotat ion. 1 *0740 1 '0721 1 *0754 I -0743 1 *0690 1 -0690 1.0695 1,0685 1,0721 --15" 15 CI-~ 1.2296, Mol. rotation. 16 -016 15 -984 16 *023 16 *005 15 952 15 -952 15 958 15 *945 15 -988 Arerage 18.05 1 1.0715 I 15.980 Less llOHz 11 -0oO 4 *980 Observations on the Xtrates Nitro-compounds and Nitrites.On placing the boiling points of the nitrates nitro-compounds and iiitrites side by side the differences between them are seen to be very remarkable thus the nitrates which are the more highly oxygenated compounds do not boil at so high a temperature as the niti-o-com-pounds whilst the nitrites which are isomeric with the latter are extremely volatile thus-B. p. B. p. Nitro-compounds. . CH3*N02. . . . LOL" C,H,-NO,. .114.5" Nitrates . CH3*O*N02. . 65' C2HI,*0*N0,. . 87.5" -_ -Difference 36" 27" 13. p. B. p. Nitro-compounds. C,H,.NO,. . 131" (CH3),C2H,*NO 140" Nitrates C3H,*09N02. . 110.5" (CH3),C2H,.0*N02. . 124" Difference . 20.5" 16' -OF NITROGEN COMPOUNDS. $23 B. p.33. p. Nitro-compounds. . CH3*NOz. . l O l ' C,E5*NOz. -114.5" Nitrites . CH,*O*NO Gas C,H6*O*N0 17" -Difference more than 101" 97.5" B. p. B. p. Nitro-compounds C3H7*NO2. . .131" (CH3),CZH3*NOz . .140" Nitrites. . C3H7*O*N0. . 44" (CH3)zCzH3*O*N0 67.5' Difference 87" 72.5" -It is also worth noticing that in the lower members of the series the difference between the boiling points is greatest; thus in the compai~ison of the nitrites and nitro-compounds methyl nitrite is a gas whilst the nit>ro-compound boils at 102"; with the ethyl-corn-pounds the diff. is 97*5" in the propyl 82" and i n the isobutyl 72.5". The same thing is seen when comparing the nitrates and nitro-corn-pounds. The densities do not vary in the same order as the boiling points, those of the nitrates being the highest.The nitrites however are considerably lower than the nitro-compounds thus-1 r o 15 Ethyl nitrate d L o 1.1159 Nitro-ethane , 1.0561 Ethyl nitrite d- 0.920 0" 0" 4" 4 Isobutyl nitrate d- 1.0334 Nitro-isobutane 0" 1.0083 Isobutyl nitrite d4-" 0.8878 4" The boiling points and densities of nitro-compounds being so very much higher than those of nitrites made it desirable to determine the molecular weight of a nitro-compound at a lower temperature than had been previously employed ; Raoult's metbod was therefore used. The experiment was made with glacial acetic acid 1.250 parts of nitroethane being added to the 100 parts of acid the result obtained for the molecular weight was 80 the theoretical number being 75, therefore notwithstanding the above peculiarities when in the liquid state nitroethane has the same molecular weight as that found by Victor Mcyer for its vapour 7.34 PERKIN TLIE MAGNETIC ROTATORY POWER Nitric A c i d .The specific magnetic rotation of this substance is very low only a little more than half that of water. The small amount of water in the specimen examined would if anything slightly reduce the rotation as will be seen further on but the maximum effect it would produce could not be more than 0.004 on the molecular rot,ation it may therefore be disregarded. Hydrated Nitric Acid. The acid exzinined contained 56.74 H,NO, and had the composition The effect of the water is to reduce the HO-NO + 2.670 mol. OH,. rotation thus-HO*NO + 2.670 OH2 = 3.656 less 2.670 OH = 2,670 HO*NO = 0.986 Pure HO*NO gave 1.180 Difference = reduction = 0.194 -It therefore appears that combination takes place as in the case of sulphuric acid (Joirr.Chem. SOC. 1886 49 783). This contractkn, however is not quite PO large as would be expected from the union of 1 mol. of water with the acid and it is very probable that for the existence of H,NO a larger percentage of water may have to be present than in the acid examined as in the case of sulphuric acid, which apparently requires a t leaat 3 mols. of water t o be added to H,S04 for the conversion of all the acid into (HO),SO. The cal-culated molecular rotatinn for H,NO would be about 1.930; the above result makes i t 1.986. The existence of such a compound as (HO),N:O cannot be regarded as improbable as we have an analogous compound in the case of orthophosphoric acid (HO),P:O and more-over there are several salts which correspond to (HO),N:O as-Trimercuric nitrate Hg3”Nz08, Tricupric nitrate Cu,”N,08, Triplumbic nitrate Pbs“NuOe, though there are no nitrates of t,he alkali metals of this type corre-sponding to the alkaline ortho-phosphates.Nitric Ethers. When nitric acid is converted into a nitric ether the change whic OF NITROGEN COMPOUNDS. 725 takes place in the rotation is very similar to that of the acids of the fatty series and shows contraction the increase of the rotation by the alcohol radical not being equal to that required €or change of compo-sition. The best compounds to compare nitric acid and its ethers with are perhaps formic acid and its ethers as formic acid contains the smallest amount of carbon.By subtracting the molecular rotation of the acids from the rotation of the ether the difference obtained for the changes of composition can easily be compared-Nitrate of methyl 2.057 Formate of methyl . 2.495 Difference for CH2. . 0.87’7 Difference for CH,. . 0.824 Nitric acid 1.180 Formic acid . 1.671 -Ordinary value for CH 1.023 Ordinary value for CH 1.023 Nitrate of ethyl 3.084 Formate of ethyl 3.564 Nitric acid 1.180 Formic acid 1.671 Difference for C,H4 . . 1.904 Difference for C2H4 . . 1.893 Ordinary value for C,H4 2.046 Ordinary -value for C2H 2.046 - -Nitrate of propyl 4.085 Formate of propjl 4.534 Nitric acid 1.180 Formic acid 1.671 Difference for C3H6 2-90 Difference for CsH6 2.863 P L-Ordinary value for CsH6 3.069 Ordinary value for C3H6 3.069 From these comparisons we see how similar the behaviour of nitric acid is to that of formic acid.If acetic acid and its ethers had been taken for comparison nearly the same amount of agreement would have been observed so thnk nitric acid may be said to behave in a manner similar to a fatty acid in respect to its formation of ethers. The only other oxygenated inorganic acid which has been examined is sulphuric acid and this also behaves like the fatty acids in reference to its methyl ether-the only ether yet examined (Jour. Chem. Xoc., 1886 49 785)-thus :-Mol. rotation. Sulphate of methyl 4.013 2) 1.698 Sulphuric acid 2.315 --CH2 0.849 1.023 Ordinary value for CH,.. VOL. LV. 3 726 PERKIN THE MAGNETIC ROTATORY POWER Ethylene Nitrate. Nitroglycol C2H,( O*N02)2. The density of this substance is higher than that of ethyl nitrate, 15" 15 as might be expected; the difference at 15" is 0.3801 for d- ; its specific rotation is slightly lower. the variation between their molecular rotations :-The following comparison shows Ethylene nitrate 3.768 Ethyl nitrate 3.084 -0 Difference for displacement of H by -O*N<o 0.684 Nitroglycerin C3h',(O'N02)s. The sp. gr. differs from that of propyl nitrate atl 15" by 0.5378 for 15" d- . 15 The relationship of the molecular rotation of this componiid to a mono- and di-nitrate will be best seen if the rotation of dinitro-trimethylene be calculated from that of dinitroethylene and used with propyl nitrate for comparison-Diff.Proplyl nitrate. . 4*085} 0.684 Trimethylene nitrate (calc.) 4.769 Nitroglycerin 5*407}0*638 From this we see that the introduction of the second NO has not produced quite such a large increase in the rotation as the first. This is strictly in accordance with displacements by hydroxyl (Jour. Chem. Soc. 1884 45 5593 where the influence on the rotation gradually diminishes with the introduction of successive groups so that the behaviour of these compounds is normal and the results agree with the constitution usually assigned to them. Had nitroglycerin contained its nitrogen in any other combination of oxygen than as - as it might if its constitution were represented as C3H2(NO2)3( OH), the rotation when compared with that of propyl nitrate would be abnormal.In the case of isobntyl nitrate the influence of the iso-group is found to assert itself. This may be seen by cornpaying it with the calculated rotation of the normal nitrate :-0 Butyl nitrate (iso) 5.180 Butyl nitrate (normal). . 5.108 -Diffeyence for iso-group . . 0.07 OF NITROGEN COMPOUNDS. 72 7 This difference is somewhat less than that usually obtained. Thus in the case of the alcohols it is about 0.144 and for paraffins, aldehydes and ethers about 0.112 (Jozcr. Chem. SOC. 1884 45, ATit.I.ites. The only compound of this class examined is isobutyl nitrite.* This was selected as being more stable and less volatile than the lower numbers of the series.The nitrogen of this substance being united to the hydrocarbon radical by oxygen as in a nitrate it may be considered in relation to isobutyl nitrate thus-550-551). Mol. rotation. Isobutyl nitrite 5,510 Isobutyl nitrate. . 5.180 Difference + 0.330 The fact that isobutyl nitrite although containing less oxygen than isobutyl nitrate and consequently of a smaller molecular weight has a higher molecular rotation is very interesting as showing that nitrogen when in an unsaturated condition affects the rotation of a, substance in a similar manner to unsaturated carbon by considerably increasing it (Jour. Chem. Hoc. 1884 45 561). This point will be referred to again further on. One of the reasons why nitrites have a much lower boiling point than nitrates may be due to their being unsaturated compounds, because we find in many cases that these have lower boiling points than saturated compounds.For example vinyl chloride is a gas; ethyl chloride boils at 12.5" ; dichlorethylene boils at 37" ; ethylene chloride at 84" &c. Nitro-compounds. These have the saome empirical composition as the nitrites but their rotations are very different thus-Propyl nitrite (cal.) 4.387 Nitropropane. . 3.819 Difference - 0.568 At first sight this might be thought to be simply due to the nitrogen in nitropropane being saturated and in the nitrite unsatu-rated and no doubt this is the chiqf cause of the variation ; but it must be borne in mind that the structures of these two compounds * Since writing the above some other nitrites have been examined which give rotations confirming thak of isobutyl nitrite.3 3 728 PERKIN THE MAGNETIC ROTATORY POWER differ the nitrogen of the nitropropane being in direct union with the carbon whilst that of the nitrite is attached to it by the inter-vention of oxygen is sufficient to account for a small part of the difference between the rotations of these bodies. 0 The influence of the group - N g o when displacing the hydrogen in paraffins is very small thus-Nitropropane. . 3.819 Propane (cal.) 3.590 Diffcwnce 0.829 With compounds of larger rotation than the above it acts very curiously actually reducing them thus chloroform has a larger rotation than ni trochloroform (ch1oropicrin)-Chloroform . 5.559 Nitrochloroform 5.384 Difference 0.175 The same thing is seen to a greater extent in the aromatic series when the nitro-compound has a much lower rotation than the hydro-carbon it is made from and in nitroparaffins it probably reduces the value of the hydrocarbon radical.As noticed on several occasions the magnetic rotation of the first and second members of a series of carbon compounds do not give numbers which bear the same close relationship to each other as those of the higher members which differ regularly by 1.023. This is also seen in the case of the nitro-compounds which vary by only 0.98, and in the nitrates which vary first by 1.025 and then by 1.00 as the following diagram will show (Fig. l) where they are compared with the formates and acetates.The circles on the dotted lines sliow the positions they w oulcl occupy if they had the ordinmy relationships. The oiidinates in this diagram are the decimal numbers only of the molecular rotations. Observations o n the R o t a t i o n of the Bases. As the values for the rotation of ammonia were obtained from its solutions in water and in alcohol it might be objected that they are not trustworthy as probably combination of the ammonia and the solvent might take place. It was for this reason that two different soivents were employed ; alcohol being taken as one the probability of the combination of ammonia with this liquid being less than with water. The quantities of the soliltions prepared were considerable, so that on taking out samples for examination no appreciable chang .H .PERKIN. *50 *40 FIG. 1 OF NITROGEN COMPOUNDS. 729 of composition would take place in the bulk from loss of ammonia. It will be observed that both solutions gave practically the same rotations for ammonia viz. 1.818 and 1.826. It would appear therefore that when ammonia is absorbed either by water or by alcohol the product simply consists of the solverit and ammonia. This is confirmed by the rotations of its nitrate and acid sulphate. I hope however to examine ammonia liquefied by pres-sure at some future time and also other easily liquefiable gases. The displacement of an atom of hydrogen in ammonia by an alcohol radical increases its rotation as would be expected but not to the full extent usual for a change of composition which is 1.023 for every CH in the homologous series.This however is not a case quite comparable with the homologous series. I n the displacement of a second atom of hydrogen in ammonia the rotation is increased proportionally more than by the first and in diethylamine i t is about the usual amount for the homologous series. In dipropylamine it is only a little less. When however we come to the displacement of the third hydrogen, a very remarkable increase of the rotation takes place marking out a clear distinction between diamines and triamines. The effect of displacing a fourth atom of hydrogen by an alcohol radical in ammonium chloride is still greater than for the displacement of the third in ammonia or what is the same thing in ammonium chloride ; this will be seen by the following comparison :-Tetrethylainmonium chloride 13.634 Triethylamine hydrochloride (cal.) 10.005 Difference for C2Ha 3.619 The following aze the results obtained with the ethylamines and propylamines showing the differences resulting from the displacements and between the variations of rotation.The displacement of hydrogen by C,H, C3H7 and CaH9 is of course as far as composition is con-cerned practically the same ns the addition of C2H4 C3H6 and CaH,. Difierence between Molecular Diff. for rotations for rotation. C2H4. each C2HI,. Ammonia N{E 1.818 3 -609 1 9’91 Ethylamine 0.262 N { } 0.803 2 9356 Diethylamine . I . . . . N{ g H 5 *662 Triethylamine. N {gt 8 *518 X 730 PERKIN THE MAGNETIC ROTATORY POKER Difference between Molecular Diff.for rotations for rotation. C3H6. each C:&. fH . 1.818 Ammocia. 2 -745 . 0.241 1.129 Propylamine 2 -986 Dipropylamine . H f Pr Tripropglamine 11 -664 So that whilst the variation of the rotakions for C,H between ethylamine and diethylamine differs by only 0.262 those between diethylamine and triethylaminc differ by no less than 0.803 ; between propylamine and dipropylamine the variation of the rotation f o r CsH6 is only 0.241 yet between dipropylamine and tripropylamine it amounts to 1.129. The relationships of the rotations of the ethylamines and pi*opyl-amines amongst themselves and to each other will be more clenrly understood by reference to Fig. 2 where they w e represented graphicali y. I n case of the displacement with isobutyl the examination of the first two only have been made but they give results much the same as in the other cases.They are however interesting as showing that the iso-radicals as compared with the normal still exert their peculiar influence on the rotation. The following is a comparison of the results obtained with these substances :-Molecular rotation. Diff. for C,H (Tso). Ammonia. . N { g 1.818 3 *874 Isobutylamine N { i(yj ] 0.370 4 *244 Diisobutylamine N { Et 9 '936 H To get the true effect of the iso-group on the rotations of these bases it would be necessary to compare them with the normal butyl-a.mines but these have not been examined; it can be shown though not very accurately by comparing them with the yropylamines in which case the difference between them should be greater than that for the value of CH,; this will be found to be the case thus W.H . P E R K I N. FIG. I. 12. a 11.0 10.0 9 .O 8.0 7.0 6 . 0 5.0 4.0 3.0 .2.0 1.0 CURVES FORMED BY THE ROTATION OF ETHYLAMINES AND PROPYLAM IN ES. FALL I N THE FREEZING POINT OF SODIUM PRODUCED BY ADDING GOLD. C . T HEYCOCK AND F. H. NEVILLE ATOMS OF GOLD PER 100 ATOMS OF SODIUM. clvs.5- were ObtairzPd. hy soci?€Zum to sat. HARRISON & SONS LITH. ST MARTINS LANE. W.C O F XITROGEN COMPOUNDS. 731 Isobutylamine . 5.692 Propylamine 4.563 1.129 Difference for CH . 1.023 Difference for iso-group. 0.106 Dipropylamine 7.549 2.387 Difference for CH x 2 . . . 2.046 Difference for two iso-groups 0.341 -Diisobntylamine 9.936 --These numbers are as close as could be expected by this method of comparison and clearly show that this iso-group irifluences the rotations of amines in the same manner as it does other classes of compounds.The results produced by the displacement of the hydrogen of ammonia by alcohol radicals stand alone ; the only other annlogous cases occur in the displacement of the hydrogens in wat,er by ethyl, when the rotations increasingly rise with each much as i n the t'wo first displacements in ammonia thus-Molecular rotation. Difference. Water 1'000} Ethyl alcohol 0 { Ethyl oxide . 0 { zk 0 *217 2*7s0} 1.997 4 3'77 And when the hydrogen in the methyl of methyl alcohol is displaced by methyl but although we at first get an increase in the rotation of this group for the first and second displa~ement~s the analogy with ammonia then fails as the introduction of a third atom of methyl does not increase the rotation to the same extent as the others do.Molecular rotation. Difference. Methyl alcohol,. HOC { 1.640 Ethyl alcohol HOC{ Ze 2.780 1 *140 1 *239 1.103 0 -099 . - 0 '136 H Isopropyl alcohol HOC Me 4 *019 Me Tertiary butyl alcohol HOC 1 1.le 5.122 1 Mf 732 PERKIN THE MAGNETIC ROTATORY POKER In aZZyZanzine we have an example of an unsaturated radical dis-placing the hydrogen of ammonia ; as in the other cases this being a first displacement the radical does not increase the rotation to the same extent it usually does in other classes of compounds thus-Increase due to C3H5 * fH 1 3.769 Ammonia f A1 Allylamine N{ II 5.587) 1H Allylacetic acid 6.426 Acetic acid.. 2.525 Increase due to C3K5 . . 3.901 -Ethyl allylacetoacetate 10.382 Ethyl acetoacetate 6.501 Increase due to C,H . . 3.881 Ethsl allylmalonate . 11.281 E thy1 m alonate 7.4 10 Increase due to C3HB . . 3.871 --If compared with propylamine the increase due to the radical being unsaturated will be seen-Allylamine 5-58 7 Propylamine. . 4.563 Difference. . 1.024 -This is about the usual difference although it is a little larger than is usually found f o r compounds containing allyl. Pentamethylenediamine is a useful example of the successive dis-placements of hydrogen by NH in paraffins.This can be seen by comparing its rotation with that of amylamine and then again with pentane. Difference for displacement of H by NH. . Pentane 5'638} 0.971 Amylamine (calculated) . 6.609 0.883 Pentamethylenediamine. . 7.492 } From this it is seen that the second displacement produces mthei OF NITROGER' COMPOUNDS. 733 less effect on the rotation than the first ; this we find to be the case in other displacements in the paraffins as in the hydroxyls of glycerin previously referred to &c. Before considering the rotations of piperidine and pyridine it will be as well to consider those of the t w o nitriles propionitrile and glutaric nitrile (cyanide of trimethylene). To compare these com-pounds it will be the simplest plan t o add 1.023 to the rotation of propionitrile which will give the value of butyronitrile viz.1.023 + 3.331 = 4,354 and both numbers will then be related to compounds of the same hydrocarbon ; we then get the following comparisons :-. 3*5901 0.764 Propane (calculated) Butyronitrile (calculated). 4.354 'I 0.782 Glutyronitrile . 5.136 I Average 0.773 I n this case the first and second displacements by CN give nearly the same numbers the second being slightly the higher ; this is excep-tional in compounds of this class and may possibly be due to some dight impurity in the glutyronitril the numbers however cannot be far from the truth. Piperidine.-The magnetic rotation of this base is very low show-ing clearly that it is a saturated compound. The following is a comparison of it with amylamine which contains two atoms more hydrogen :-Amylamine .6.609 Yiperidine 5.810 0.799 This is a rather larger difference than is usually found between a saturated fatty compound and a saturated ving compound and is more than the value of H2(0.508) by which they differ. A number of ring compounds discovered by my son have had their magnetic rotation determined and will show this ; those containing a methyl group will require to have the usual amount deducted from them as it has been shown that this increases the rotation by about 0.111 as in iso- and secondary compounds. Valeric acid C,H,,O . 5.513 Tetramethylenecarboxylic acid C5H,O2 . 5.049 Difference 0.46 734 PERKIN THE MAGNETIC ROTATORY POWER mnanthylic acid C,H140 . Methylpentamethylenecarboxylic acid C,H,,O,.. Less . Difference Caprylic acid C,HI602 Methylhexamethylenecarboxylic acid C,H1402 . . Less. . Difference E thy1 propylmalonate C6H,04E t Ethyl tetraniethylenecarboxylate C,H,04Et2 . Difference The average of these differences is 0.471 not very value of H by which they differ but only a little more difference found between amylamine and piperidine ; 7.552 6.928 0-624 0.111 0.513 8.565 7.9 74 0-591 0,111 0.480 10.370 9.940 0.430 far from the than half the in this case, ---however we are dealing with a base and it has heen seen that sub-stances of this class are somewhat exceptional in their behavionr; this therefore may be the cause of the variation. Pyridine has also a very low rotation if considered in relation to aniline from which it differs only by CH, thus-Aniline 16.162 Py r idi ne 8.7 6 1 Difference 7.401 in fact it is lower than benzene from which it differs only by having N suhstitnted for CH and the value of this element as ""is not very different from that of CH (see p.738). Benzene 11.297 Pyridine 8.761 2.536 Less f o r H 0.254 Difference. 2.282 This is very remarkable especially when we find that the intro-duction of NH into benzene increases its rotation so much OF NITROGEN COMPOUNDS. 735 Aniline . 16.1 62 Benzeue 11.297 Influence of NH 4.865 By comparing pyridine with piperidine the effect of the difference of H6 by which they vary in composition will be seen. Pyridine 8.761 Piperidine 5.810 2.951 This shows how much the higher of the two the rotation of pyridine is through being an unsaturated compound although of less molecular weight than piperidine.This is not very far from three times the difference existing be tween saturated and unsaturated compounds differing from each other by H,. Isobutylarnine with Water and Alcohol.-As aqueous and alcoholic ammonia appear to be simply solutions of NH in these solvents it was thought that it would be well to see if a monamine acted in the same way. Solutions consisting of equal volumes of isobutylamine and water and isobutylamine and alcohol a t 15" were therefore made ; in both cases heat was evolved and contraction took place ; the lnttei. will be seen by a comparison of the found and calculated den-sities of these mixtures.Wafer a d Isobutylamiiie. Density found 0.9002 Average density 0.8681 Difference due to contraction . 0.0321 Alcohol (absolde) and Isobutylamine (the mean of two preparations). Density found 0.7791 Average density. 0.7656 Difference due to contraction 0.013.5 On comparing the magnetic rotations of these mixtures it will be found that a small amount of combination is indicat,ed. Equal Volumes of Water and Isobutylarnine. Molecular rotation of mixture calculated Molecular rotation of mixture found . from constituents 11.200 11.099 Difference 0.10 736 PERKIX THE MAGNETIC ROTATORY POWER Equal Volumes of Alcohol and Isobutylamine. Molecular rotation of mixture calculated Molecular rotation of mixture found from constituents.. 10.459 10.361 -Difference. . 0.098 Fipeyidine and Water.-This base has a great attraction for water, and considerable heat is evolved on mixing these two substances. The mixture examined had the composition C,H,,N + OH,. The following is a comparison of the average and found densities of the mixture :-Density found 0.9133 Average density 0.8897 Difference due to contraction. 0.0236 This is a considerable contraction for the small quantity of water The magnetic rotation of this also shows used viz. 17-07 per cent. a small amount of combination. Molecular rotation of mixture calculated from constituents . 6.810 Molecular rotation found 6.724 Difference 0.086 The rotation of isobutylamine with water and alcohol and of piperidine with water therefore indicates that these mixtures contain a small quantity of unstable compounds of the composition-the amount most probably varying with the temperature as was found in the examination of mixtures of ddehyde with water and alcohol (Jour.Chew,. SOC. 1887 51 815-819) and of course may be the case with solutions of ammonia but if so the amount entering into com-bination a t the temperatures at which the rotations were observed was too small to appreciably affect them. Value of Nitrogen. From the foregoing results it is possible to get an estimate of the amount of influence nitrogen has on the magnetic rotation of bodies. I n the first place it will be as well to consider it as it exists i OF NITROGEN CONPOUNDS. 737 nitrates where it is in a pentavalent condition.If these bodies have the composition RO - N g 0 it will be necessary to subtract from a nitrate the value of the radical also that of one oxygen as found in the hydroxyl of acids namely 0.137 and for the two oxygens which are fully saturated with nitrogen that is the values which this element has when fully saturated with carbon viz. 0.261 which is probably the same as if saturated with nitrogen. We then get from ethyl and propyl nitrates the following results :-0 Ethyl nitrate 3084 O2 saturated by N 0.522 2.959 Ethyl 2.300 0 in hydroxyl of acids 0.137 NV 0.125 - - I Propyl nitrate 4.085 Propyl . 3.323 02. 0 . 0.137 NV 0,103 These numbers are not far apart and show that the value of nitro-gen when saturated is very low namely about 0.114.This method of calculation cannot be satisfactorily applied to nitro-compounds because we have no very definite information as to the effect produced on the rotation when -N<; is in direct union with the carbon of an alcohol radical except that it appears to reduce the value of the hydrocarbon radical to a smitll extent. We can get a value for it in a similar manner to that used with nitrates taking the constitution to be In the .n,itrites the nitrogen is trivalent. R.0 - NzO. It will be more simple and perhaps more correct if the rotation of propyl nitrite be used in this estimation ; this is easily obtained from that of isobutyl nitrite by adding to the rot>ation of propyl nitrate the difference found between isobutyl nitrite and nitrate ; this is 0.330.Propyl nitrite will therefore be 4.085 (propyl nitrate) + 0,330 = 4.415 i 3 8 PERKIN THE MAGYETIC ROTATORY POWER Propyl nitrite . 4.415 0 saturated with N C.261 3.721 Propyl 3.323 0-137 } 0 as in hydroxyl of acids. _-N ‘ ” . . 0.694 The rotation of nitrogen in bases can be found approximately by subtracting the rotation of a paraffin from a base and then the value of H from the remainder. Amylamine (calculated) 6.609 Pentane 5.638 NH 0.971 Less H 0.254 N”’ 0.717 --Thc cyanides also can be used to give a value thus-. } 3.331 Ethyl cyanide Isopronitryl Less ethyl 2.300 CN 1.031 Less C . 0.515 Nf” 0.516 --Taking trimethyiene cyanide we get-Trimethylene cyanide 5.136 3069 (CN) 2.067 Trimethylene CH X 3 -Less C2 1.030 N,”’ 1.037 N”’ 0.518 -Average value of N’” = 0.611.In the cyanides the value comes a little lower than in the other pro-ducts but it is possible that the value of carbon subtracted is not quite correct as we do not know its true value when three-fourths saturated with nitrogen; though of course in all the values found for the elements they are only approximate and not absolute as they are found to vary slightly in different series of compoundR and in some instances they vary considerably. These numbers however show th OF NITROGEN COMPOUNDS. 739 interesting fact that unsaturated nitrogen (N”’) has a very much greater influence on the magnetic rotation of compounds containing it than when it is saturated (N’) ; this is about 0.5 taking the average of all the values given and practically half the amount of the difference usually found between saturated and unsaturated carbon compounds (differing by H2).The clearest evidence of this is perhaps after all best seen in the comparison between a nitrite and nitro-compound where both have the same composition the variation due to difference of constitution probably not reducing the rotation of the nitro-compounds by more than about 0.1 ; this would then leave 0.468 between these compounds in favour of N”’ over NV. Hydrochloric Hydrobromic and Hydriodic Acids. When studying the magnetic rotations of the aqueous solutions of these acids one striking fact is noticed and that is the magnitude of the numbers as compared with those deduced from the rotations of the chlorides bromides and iodides of the alcohol radicals.The latter however refer to the acid in combination and not in the free state but the addition to them of about 0.2 will make the necessary correction for this. The numbers are as follows :-Jn combina- In free tim. state. Hydrochloric acid C1 1.733 + H 0.254 = 1.987 2.187 Hydrobromic , . . Br 3.362 + H 0.254 = 3.816 4.016 Hydriodic , . . I 7.727 + H 0.254 = 8.011 8211 Concentrated aqueous solutions of these acids were first examined, and these gave molecular rotations for the pure acids nearly twice as large as the above; a more dilute solution of one of the acids was then examined and this gave a still higher result and it soon became evident that acids in different states of concentration gave different results ; it appears necessary therefore to examine a graduated series of each acid commencing with very concentrated and finishing with dilute solutions.The following are the results obtained :-Mol. rotation of HC1. 4.045 . . 36.5 , 4.215 Hydrochloric acid . . . . 4-1.70 per cent. HC1 7 7 9 9 9 . . . . 30-86 , 7 9 4.303 7 ) . . . . 25.60 ) , 4.405 , . . . . 15.63 , ?) 4.41 740 PEltKIN THE MAGSWIG ROTATORY P3WER Mol. rotation of HBr. Hydrobromic acid 65.59 per cent. HBr 7.669 9 9 56.00 , 7 8.061 7 39.71 , 9 8.415 Y 24.60 , * 8.547 19 . * . 35-47 , 9 ) 8.519 Mol. rotation of HI. Hydriodic acid . 67.02 per cent. HI 1'7.769 , 65.10 , 7 17.868 7 7 61.97 , 9 9 18.117 19 56.78 , 9 18.308 7 42.70 , Y 18-403 7 9 31.77 ,) 7 18,451 9 20.77 , 9 9 18.428 .. . . . . I n all these series it is seen that the molecular rotations found for the pure acids first rise as the solution is diluted and then become practically stationary the variations of the last two numbers in each series not being more than might be expected from experinierital errors. These results have been graphically represented on Fig. 3 ; in this, t\To curves start from the calculated values of each acid one repre-sentirig the rotations in reference to the percentage of the acids the other in reference to the molecula'r composition of the solution The registers for these are both given on the top of the diagram whilst those for the rotations are given in three columns one on the left side and two on the right side each headed with the formula of the acid it refers to.This aimmgement was adopted to get the three sets of curves as nearly as possible in juxtaposition. It will be noticed how great a sirriilarity there is i n the character of these cuyves, especially those corresponding to the molecular proportions ; each rising rapidly from the calculated rotations of the acids and then gradually turning off to a horizontal line. The difference of the highest rotation represented by the horizontal lines from the calcu-lated is in all cases more t'hnn twice as large as the latter thus-HCl. HBr HI. Highest number . . . . . . . 4.412 8.533 18.435 Calculated number 2.187 4.01 6 8.211 Difference 2 225 4.517 10.224 A!1 the rotations of these acids closely approach the horizontal line W OF NITROGEN COMPOUNDS.741 and therefore their highest rotations when they contain from 6 to 7 mols. of water. It is very difficult to form a conception of the meaning of these results so far as experiments have gone. Acids when diluted with water either combine with it and thus cause a reduction in the rotation as sulphuric (J. Chenz. Xoc. 1886 49 782-784) and nitric acids or are not influenced by it as in the case of formic acetic, propionic (J. Chsm. SOC. 18S6 49 778-781) glutaric acids &c., but in no case does an increase take place; such a result would indicate dissociation. It was thought that something of this kind might take place the very concentrated acids possibly containing complex molecules built up of several molecules of the acids and breaking down on dilution ; thus the highest rotations would be the correct ones foi.the simple acids but the difficulty in the way of this is that in compounds in which the halogens must exist in single atoms the rotations of the acids deduced from them are only half those found in the examination of the dilute solutions. On account of the difficulty of finding an explanation experimenhs were made to see if the solvent played any part in this matter; it was however, found very difficult to get a liquid which would dissolve these acids in sufficient quantity and at the same time not to be affected by them. Acetic anhydride for example was found to change rapidly into acetic acid and acetyl chloride o r bromide according as it was saturated with hydrochloric or hydrobromic acids.Heptnne was found to be only capable of dissolving about 1 per cent of hydrochloric acid. At last isoamyl oxide was tried and this dissolved about 18 per cent. of hydrobromic acid and 13 per cent. of hydro-chloric acid. Unfortunately hydrobromic acid was found t o gradually act upon it so that it could not be examined in this solvent. Hydro-chloric acid however has no influence upon it. Its solution in this substance was therefore examined. Two preparations were made and these gave the following results :-Mol. rotation. HCl. 2.211 I. Containing 10.68 per cent. HCl gave . 11. , 12.82 9 . 2.265 Y Y Average. . 2.833 Calculated rotation 2.187 Difference 0.051 These two results are very interesting as they are quite different from those obt,ained on the examination of aqueous solutions and are VOL.LT. 3 742 PERKIN THE MAGNETIC ROTATORY POWER as close t o the calculated as could be expected considering the small percentage of acid contained in the specimens measured. No doubt if hydrobroinic and hydriodic acids could have been examined in the mme way analogous results would have been obtained. It appears therefore that the calculated numbers for the halogen acids are practically the correct ones and that the high results obtained from the aqueous *ids are abnormal and in some unaccountable way caused by the presence of water though as already mentioned, chemical union with water would n o t increase b u t reduce the rotations of the acid according to all previous experiments.G. Lemoine (Ann. Chem. Phys. [.5] 12 239) as well as Bertholet, have noticed the peculiar fact that whilst gaseous hydriodic acid is decomposed by light the aqueous solutions are not this seems to indicate that water has some peculiar influence upon this acid. Salts of Ammonia and Compound Ammonias. The results of the examination of the solutions of the salts of ammonia and the compound ammonias containing hydrochloric, hydrobromic and hydriodic acids are not less remarkable than those of the acids themselves except that the effect of various degrees of dilution does not influence the molecular rotation of the salts; this will be seen from the results of the examination of the four aqueous solutions of ammonium iodide and the two of ammonium bromide as given in the following tables :-Mol.rotation. NH4L 19.936 11. , 58.46 , 20.032 111. , 54-64 , 19.971 IV. , 30.50 , 20-049 I. NHJ 60.44 per cent . Average 19.996 Mol. rotation. NH,Br. 10.159 11. , 85.00 , 10.196 I. NH,Br 40.42 per cent. Average 10.1 7 7 From these it will be seen that although the solutions vary very considerably in strength yet they give numbers which are practically the same in both instances. This fact should be borne in mind whe OF NITROGEN COMPOUNDS. 743 considering the results of the examination of the aqueous solutions of otLer salts referred to in this paper. On considering the rotations obtained with solutions of the different salis formed by ammonia and the compound ammonias with the halogen acids it will be useful to find what their calculated rotations are so as to compare them.The rotation of the acids taken in this place will have t,o be those found for them in combination already given on page 739 then as ammonia and the compound ammonias contain unsaturated nitrogen which will become saturated on their union with the above acids, this as shown elsewhere will reduce the rotation by about 0.5. The rotations of these salts may then be calculated thus :-Cdculated. Found. N4HCl = HC11.987 + NH 1 *818 - 0.5 . . . . 4 *305 6 *096 KH Kt2HCl = HC11 '987 + NHEt2 5 '662 - 0 - 5 . . . . . . 9 -895 NHZEtHCl = HC1 1.987 -I- NH,Et 3.609 - 0.5 . . . . NEt3HC1 8.518 - 0 ' 5 .. . . . . C,H1INHCl= HCl 1.987 + C,HiiN 5'810 - 0 . 5 . . . . . 6 -096 7 *997 8 '149 = HC1 1 -987 + NEt 11 -005 8.297 11 '733 10*034 NH,Br = HBr3.816 + NH3 1.818 - 0.5 . . . . 6-134 10.177 NH,I = Hi 8'011 + KH 1.818 - 0.5 10.329 19.956 From the above it will be seen that the experimental results arc; greatly in excess of the calculated and on examining them they are found to he nearly equal to those which would result from simply adding together the rotations of the bases and the highest or abnorrnnl rotations of the acids no allowance being made for combi-nation or saturation of nitrogen :-Abnormal rotation. Calculated. Found. NH4Cl = HC14.412 + NH3 1.818. 6-230 6.096 NH2EtHC1 = HC14.412 -t NH2Et 3.609. 7.997 NHEt2HC1 = HCI 4.412 + NHEt2 5.662 .. . . . . . . . 9.896 NEt.,HCl = HCl4.412 + NEt3 8 '518 . . . . . . . . . 12.930 11.739 8'021 10.074 C5H11NHC1 = HC14 -412 + C,HiiN 5 '810. . . a . . 10'222 10 -034 XH4Br = HBr8-533 + NH 1.818 . 10.351 10.177 NH41 = HI 18.436 + NH 1 *818 . . . . . . . . . 20.253 19-996 It is thus seen how little the numbers ohtained in this manner vary from those found except in the case of triethylamine hydrochloride, which will be referred to further on. The hydrochloride of piperi-dine which is analogous to a diamine hehaves in the same way as salts of that class. The only explanation I can find for these remarkable results is that these salts when in solution are almost 3 ~ 144 PERKIS TRE MAGNETIC ROTATORY POmR entirely dissociated into their acids and bases the acids owing to the presence of water acquiring the high or abnormal values ; the dlight difference between the calculated and expefimerrfnl numbers being *due to the presence of a very small qnantity of nndissociated salt,.I n the case of triethylamine the amount of dissociation is evidently considerably less than in the other salts the third molecule of ethyl it contains adding to its stability. This is on17 what might be expected as the addition of a fourth molecule yields the remark-ably stable chloride of tetrethj-la,mmoniam. This has also been examined and probably does not dissociate when in solution or only to a small extent. The rotations obtained from the chloride of tetrethylammoriium and the hydrochlorides of dethylamine and ammonia have been plotted out side by side with the calculated numbers in Fig.4. From this i t will be seen that the calculated numbers form a curved line (similar to the *ethylamines Fig. 2, facing p. 730) but straightens a little between triethylamine hydro-chloride and triethylammonium chloride whilst the experimental form a straight line; the latter owing to the dissociation of the salts, is considerably far apart from the cnr-ved line in the lower portion of the figure but both meet a t the top a t a point representing tetrethyl-ammonium chloride. It will also be seen that the distance between the curved and straight lines is less a t the points representing tri-ethylamine hydrochloride than a t those representing the other hydro-chlorides thus showing a smaller amount of dissociation.From the different results obtained from solutions of hydrochloric acid in two kinds of solvents. it appeared desirable to examine some of these salts in solvents other than water. Solutions of diethyl-amine hydrochloride and ammonium iodide in absoluhe alcohol were therefore employed as no other srxihblc solvent could be found but from the rotations obtained dissociation evidently takes place though not to qnite so large an extent as when water is used as the following numbers show 2-Mol. rotation. Mol. rotation. Alcoholic Aqueous solution. solution. Calculated. Diethylamine hydrochloride . . 9-674 9.896 7.149 Ammonium iodide . . . . . . . . . . 18-95 20.032 10.409 All these results made it important to sludy the behaviour of some other salts of ammonium when in soiution and for this purpose aqueous solutions of the nitrate acid sulphate and neutral sulphate of ammonium were emploJ,ed.Kitrate of ammonium is not supposed. to dissociate to any appreciable extent nor is i t likely that the acid sulphate would ; the neutral sulphate however is known to do so t W H . P E R K I N . FIG. 4. CURVES SHOW I NG ROTATIO N S I N DICATI NG DlSSOC I AT1 ON OF HYDROCHLORIDES WHEN IN SOLUTION. 12. 11. lo. 9 . 7 . 0 6 . U 5 . 0 FALL I N THE FREEZING POINT OF SODIUM PRODUCED BY ADDING GOLD. C . T HEYCOCK AND F. H. NEVILLE ATOMS OF GOLD PER 100 ATOMS OF SODIUM. clvs.5- were ObtairzPd. hy soci?€Zum to sat. HARRISON & SONS LITH. ST MARTINS LANE. W.C OF NITROGEN COMPOUNDS. 745 some extent as it gives off some of its ammonia when its solution is boiled.The calculated rotations for these 8alt.s compared with the experi-mental rotation are a,s follows :-Nitrate of' Ammonium. HN0j.e 1.180 NH3 1.818 Less 0.2 reduction due to combination and 2.998 0.5 for the nitrogen being saturated = 0.700 2.298 Pound . 2-320 Difference . 0.032 - - 0.7 } -Acid Sulphate of Ammonium. H2S04 . 2.315 NH . 1.818 4.133 Less 0.7 aa above 0.700 3.433 Found . 3.455 Difference 0.022 -Neutral Sulphute of Anzmoniurn. HZSO . 2.315 (NH& . 3.636 -5.951 Less 0.7 as above x 2 1.400 4.551 Found 4.980 Difference 0.431 --From this it is seen that the nitrate and acid sulphate of ammonium give resnlts very nearly identical with those calculated.This is valuable in two ways-first inasmuch as it shows the method of calculating the rotation of these salts to be trustworthy ; and seconcily 746 PERKIN THE MAGNETIC ROTATORY POWER that the very high numbers obtained by the halogen acids and their salts with ammonia and compound ammonias are abnormal. The rotation of %he neutral sulphate of ammoni-am is rather higher than the calculated probably the latter is a rittle low as the intro-duction of a second ammonia would most likely be attended with a slightly smaller amount.of change than that represented by 0.7 ; it would not however nearly account for all the difference found which is no doubt due to a certain amount of dissociation of the salt. It is very probable that the determination of the magnetic rotations of salts in solution may be of value in distinguishing between those salts that do and those that do not dissociate in the presence of water as well as to give an idea of the extent of dissociation.With regard t o the foregoing resalts it was thought that the numbers obtained for the heat of neutralisation of the salts under consideration might in some way correspond with those of the magnetic rotations ; they do uot appear however to beer in the least upon this subject chloride of ammonium and the hydrochlorides of the ethylamines giving numbers close t o those obtained for the nitrate and sulphate of ammonium. Triethylamine hydrochloride is also a iurther exception as it gives a very low number for its heat of neutralisation ; this is quite contrary to the results of the magnetic rotation which show that this salt exists in a less dissociated con-dition when in solution tlian the other hydrochlorides and therefore would be expected to give higher numbers.The following table gives the numbers obtained for the heat of neutralisation of most of the salts examined :-2(NH, 2(NH,Et + HC1) = 26,880 ,, 2(NHEt2 + HC1) = 23,620 ,, 2(NEt3 + HCl) = 17,480 ,, 2(NH + HNOs) = 24,644cal. 2(NH3 + H,SO,) = 28,152 ,, The principal results of this research may be briefly summed up as Nitric acid when diluted with water combines with it forming an + HC1) = 24,544 cal. follows :-N:O corresponding to orthophosphoric acid HO P:O. KO HO ,,> Nitric acid forms ethers in an analogous way to sulphuric and the fatty acids that is with condensation.Unsaturated nitrogen N"' acts in a manner analogous to nnsatu-rated carbon the rota,tions of compounds in which it exists being considerably higher than those containing the saturated element OF NITROGEN COMPOUNDS. 747 The low rotations of nitro-compounds as compared with those of the nitrites is chiefly due to the former containing saturated and the latter unsaturated riitrogeri. That aqueous and alcoholic ammonia a t the ordinary temperature, appear t o consist of solutions of NH only ; but in the case of aqueous and alcoholic solutions of isobutylamine and aqueous solutions of piperidine a small amount of combination takes place with these solrents at ordinary temperatures. That in the displacement of the hydrogen in ammonia by alcohol radicnls the rotation is not increased by the usual amount due to the change of composition for the first, but it increases for the second, and becomes very large for the third displacement and in the displace-ment of the fourth hydrogen in ammonium salts it is still larger.The introduction of iso-radicalls increases the rotation more than the normal ones to quite the usual extent. Allylamine behaves like other unsaturated compounds giving a considerably higher rotation than tihe corresponding saturated base, prop ylamine. Pentamethylenediamine shows that the effect of a second displace-ment of hydrogen in paraffins by NH is to produce slightly less inflnence on the rotation than the first. Piperidine has a rotation showing thatl it is a saturated compound ; it is however slightly lower than that nsually found for saturated ring-compounds when compared with paraffin-derivatives.Hydrochloric acid when examined in its solution in amyl oxide, gives a rotation practically the same as that found for its elements when in compounds that is H in paraffins and C1 in the chlorides of the alcohol radicals with the addition necessa,ry to represent it in the free state 2.238 being found and 2.187 calculated. The solutions of hydrochloric acid in water give abuormally high rotations for this acid increasing up to certain limits wit'h the dilution of the solution the highest rotation being more than double that OC the calculated. Aqueous solutions of hydrobromic and hydriodic acids also behave in an abnormal manner like those of hydrochloric acid the results being rather more strongly marked.This cannot be explained on the assumption that the acids combine with water such a result would lower instead of increase the rotation. The rotation of ammonium salts when in aqueous solution is not influenced by the strength of the solution. The salts of ammonia and the compound ammonias with hydro-chloric hydrobromic and hydriodic acids when in aqueous solutions give very high rotations which can only be explained on the assump-tion that they are almost entirely in a state of dissociation. Thei 748 PERKIN THE MAGNETIC ROTATORY POWER acids. on account of the water present. would then possess the abnormal rotations referred to above. amd this would give the solutions their high values .Alcoholic solutions of ammonium iodide and diethylamine hydrochloride bebave like the aqueous. but the rotations are not quite so high. showing less dissociatiou . Triethylamine hydrochloride does not dissociate nearly so much as the other hydrochlorides. and the chloride of tetrethglammonium is thought not t o dissociate at all. or only very slightly. when in aqueous solutiori . Aqueous solutions of the nitrate and of the acid snlphate of am-monium give normal rotations. showing no appreciable amount of dissociation . The neutral sulphate. however. gives slightly high rotations. clearly indicating that it does dissociate to a small extent when dissolved in water . The following is a list of the substances examined.with their molecular rotations. and the numbers of the pages where they are referred to in this paper :-Substance . Molecular rotation . Page . Nitric acid Orthonitric wid . Methyl nitrate Ethyl nitrate Propyl nitrate Isobutyl nitrate . Ethylene nitrate Isobutyl nitrite Nitroglycerin Nitromethane Nitroethsne Nitropropane . Chloropicrin Ammonia (aqueous solution) Ammonia (alcoholic solution) Ethylamine Propylarnine Diethylamine . Triethy lamine . Dipropylamine Tripropy lamine Isobutylamine Isohutplaniine (aqueous solution) Inobutylamine (alcoholic solution) Diisobutylamine 1.180 1 '930 2.057 3 -084 4 -085 5 -180 3 *768 5 -4Q5 5 *510 1 Ti58 2 *a37 3 -819 5 *384 1 *810 1'826 3.609 5 -662 8.518 4 '563 7 -549 11 * 664 5 %92 5 *567 5 -593 9 -936 680.'724. 725 681. 724 682. 722. 725 682. 722. 725 683. 722. 725 683.722. 726 684. 726 685. '726 686. 723. 727 687. 722. 723 687. 722. 723 688. 722. 727 689. 728 689. 728 690. 728 691. 728 691. 728 692. 728 692. 730 693. 730 694. 730 694. 730 695. '735 696. 735 697. 73 OF NITROGEN COMPOUNDS. 749 Substance. Molecular rotation. Allylr~mine Pent,arnet Lylenediamine Piperidine Piperidine (aqueoxs solution). . Pyridine 5-587 7 *498 5 *810 5.724 8 -761 Propionitrile 3 '331 Trimethylene cyanide .I 5 '136 1 Ammonium chloride Ethylamine hydrochloride (in aqueous solution). . Diethylamine ) 9 ) . . . . .. . . Diethylamine 7 7 (in alcoholic solution) Tetrethylammonium chloride ,) 7 Piperidine hydrochloride J 7 , Ammonium n i h t e 7 ) ,) acid sulphate 7 , eulphate 97 9 ) Sulphuric acid Triethylamine ) (in aqueous solution) )> ' 6-096 7 -997 9 '896 9 -674 11 -739 13.624 10 a34 2.320 3 '455 4 980 2 -315 Ammonium bromide (NH,Br 4042 per 92 , (NH,Br25 Ammonium Iodide (NH41 = 60.44 . . . . ) 7 (NH,I = 54.64 . . . . ) 9 ) (NH,I = 30'5 . . . . ) Hydrochloric acid (HCl = 41.70 per cent. sol.) J ) (HC1 = 36'5 ) 97 (HC1 = 30.86 ) 7) (HCl = 25.6 ) 77 (HC1 = 15.63 ) ,7 2 9 9 ,) (HC1 = 1068 ) ) Hydrobromic acid (HBr = 65'59 per cent.) 9 7 (HBr = 56'0 ) 7 9 (HBr = 39.71 ) (HBr = 248.6 ) 9 (HBr = 15.47 ) . . . .(HI = 65.1 ) . . . . (HI = 61.9'7 ) . . . . (HI = 82.7 ) . . . . (HI = 31.77 ) . . . . (HI = 20.77 ) 7 9 (NH41 = 58.46 . . . . ) Ammonium Todide in alcohol (NB,I = 22.10 per cent.) . . . . . . . . . . . . . . . . Hydrochloric acid in isoamyl oxide (HC1 = 12.82 p. c.) ?7 Hydriodic acid (HI = 67'02 per cent.) . . . . (HI = 56'78 ) . 19 -936 20 -032 19 *971 20 a 049 18 -955 1 4.045 4 -215 4 -303 4 '405 4.419 2 *265 2.211 7 *669 8 *061 8 *425 8.547 8.519 17 *769 17 * 868 18,117 18 -308 18.403 18 -451 18.428 Page. 697,732 698 732 699 733 700,736 700,7U 70l7 733 '102,733 712 743 '713,743 713,743 '714 7M 715 744 715,729 716,743 721.745 721 745 722,745 725,745 716 '742 717,742 718,742 718 742 719 742 720 742 720 744 702,739 '703,739 704 739 704,739 705 74.1 705 741 706 740 706 740 707 740 707 740 708 740 708 740 709,740 '709 740 ?'lo7 740 710,740 711 740 '703 739 711 74

ISSN:0368-1645    

DOI:10.1039/CT8895500680

出版商:RSC    

年代:1889

数据来源: RSC