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Proceedings of the Chemical Society, Vol. 12, No. 171 |
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Proceedings of the Chemical Society, London,
Volume 12,
Issue 171,
1896,
Page 225-240
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摘要:
Issued 12/12/1896. PROCEEDINGS OF THE CHEMICAL SOCIETY. EDITED BY THE SECRETARIES. Dec. 3rd, 1896. Mi*. A. G. Vernon Harcourt, President, in the Chair. Certificates were read for the first time in favour of Messrs. James Herbert Brown, Dallas Place, Lancaster ; John Wallis Dodg-son, B.Sc., 47, Hirwain Road, Aberdare, Glamorgan ; Lawrence Dufty, 33, Broomhall Place, Sheffield ; Joseph Lake Gibbons, West Carlton Street, Blyth ; Alexander William Gilbody, M.Sc., Ph.D., Owens College, Manchester ; Harold Walter Gough, B.A., 73, Billing Road, Northampton ; Ernald George Justinian Hartley, B.A., Whea- ton Aston Hall, Stafford ; Charles Henry Martin, 14, dldred Street Crescent, Salford ; William James Stainer, B.A., 3, Havelock Road, Stanford Avenue, Brighton ; Samuel Matthew Walford, 62, Bloom Street, Stockport ; James Wallace Walker., M.A., Ph.D., University College, London.The following were duly elected Fellows of the Society: Henry Edward Aykroyd, William Ballingall, M.A.,Gopal Chandra Bauerfee, Charles Bnthurst, B.A., Lauritz Hansen Bay, Charles Edward Bromne, B.Sc., Walter William Cobb, M.A., George Harold Cross, B.Sc., William Duncan, Walter John Elliott, M.A., Eric David Ewen, John Thomas Fleet, George George, Arthur Croft Hill, B.A., Charles Alexander Hill, John William Hinchley, William Trevor Lawrence, B.A., Robert Dexter Littlefield, Thomas Henry Lloyd, Thomas William Lockwood, Hugh Manners, M.A., B.Sc., Edward Seaborn Marks, Arthur Stanley Mayfield, William M. Miller, Landoii Clarence Moore, Francis Ambrose Moss, Herbert William Mow, Joseph Terrence de la Mothe, Alexander Henry Mitchell Muter, 226 William Harrison Pearsn.11, Henry William Potts, Frederick Belding Power, Ph.D., William Russell, Arthur JMwin Ssville, Herbert Cecil Seabrooke, Kotaro Shimomura, B.S:., William Horace Sodeau, B.Sc., Charles Thompson, B.Sc., William Henr,y Walker, TVilliam Watson, MA., Edwin Whitfield Wheelwright, B.A., Ph.D., John Inctus Whimster, John Harrison Wigner, Ph.D., Alfred James Wilcox.Of the following papers those marked * were read. *156. Constitution and colonr.” By Arthur G. Green. In a scheme for the qualitative analysis of the coal-tar colouying matters published in 1893 (J. Xoc. Chenz. Ind., 1893, 12, 3), the author pointed out that the leuco-compounds of various dye-stuffs exhibit a striking difference of behaviour on exposure to air.Leaving out of account those which are completely split up by I-eduction (vie., azo-, nitro-, and nitroso-colours), it is possible, by means of this reaction, to classify colouring matters into two groups, viz. :-I. Colours whose leuco-compounds are not readily reoxidised on exposure to air. 11. Colours whose leuco-compounds are rapidly reoxidised on exposure to air. Group I comprises all the colouring matters of the triphenyl- methane series, the phthaleins or pyrone colours, indophenols, and indamines. Group I1 comprises the indigo class, the azines, azonium colours, oxazines, thiazines, acridine colours, thinzol colours, quino-line colours, oxyauthraquinone cplours, and certain colouring matters of unknown constitution.In explanation of the cause underlying this difference of behaviour, the aut>hor, in 1892, put forward the suggestion (Proc., 1892, 8, 195) that, assumiiig the correctness of tlie “ qEinonoid ” theory of colour (Armstrong, Proc., 1888, 4, 27; 1892, 8,101, 143, 189, and 194; 1893, 9, 52 and 206), the colouring matters of the first group might, be regarded as paya-pinolioid =/---‘--. of the second group as \=/--’ ortho-qzhionoid \--/. In the present paper, this view is more fully discussed, and further evidence is brought forward in confirmation of it, An examination of th4 members of the two groups shows that, whilst nearly all the colouring matters of Group I are compounds substituted in the para-position alone, no plain para-substituted compounds are found in Group I1; on the other hand, whilst Group I1 contains compounds substitated in the ortho-position alone (e.g., indigo) and compounds substituted in both positions, uo plain ortho-substituted compounds are to be found in Group I.Therefore, if 227 +he “ quinonoid ” theory of colour be accepted, it follows that dye- stuffs, which, from their constitution, must be ortho-quinonoid, only occur in Group 11,whilst those which must be para-quinonoid only occur in Group I. In Group I, the theory agrees in all cases with the usually accepted constitution of the colours. In Group 11,when it is not in accord with the usually accepted view, the ortho-quinoaoid formulze give as good, or better, interpretations to the properties of the colouring matters, than fhe para-quinonoid formula? previously assigned them.It would be anticipated, from the well-known inter-relationship of ortho-substituents, that two groups occurring in a11 ortho-position to each other would have a greater tendency to enter into a more intimate union, and therefore would be more oxidisable than if they stood in the para-position. The stability towards acids of the colouring matters of the methylene-blue and safranine series, and the oxidisability of their leuco-compounds, compared with the extreme instability to acids of the parent indamines (parxquinone-imides) and non-oxidisability of their leuco-compounds, forcibly suggest a change of type.The tendency exhibited by many azines and oxazines to form amido-derivatives by addition, as in the case of Meldola’s blue, can only receive an explanation by the assumption of an ortho-quinonoid structure, since, in the naphthalene nucleus, where the substitution takes place, a para-quinonoid structure is not possible. DISCUSSION. Dr. KIPPIKGsaid that Mr. Green’s classification of certain dye- stuffs into derivatives of ortho- and of para-quinones respectively, being based solely npon the rapidity with which the corresponding leuco-compounds undergo aerial oxidation, it would add to the interest af his communication if he could define more exactly the words “easily oxidised ” by introducing the element of time ; for the rapidity of oxidation of all the leuco-compounds of one class would probably not be the same, and consequenily those reduction products of paraquinones which oxidised most easily might do so more rapidly than the leuco-compounds of some of the orthoquinones.Should this never, or rarely, occur, Mr. Green’s classification would be extremely useful, but as it does not even include all dye-stuffs, it cannot be regarded a,s affording any support to the view held by Dr. Armstrong, namely, that aZZ coloured carbon compounds have a yuiiionoid structure. This view, attractive though it may he, and supported by the numerous examples which have been brought under notice, is nevertheless untenable : that all quinones and their derivatives are coloured may be true, but to assume that all coloured substances are quinones would necessitate in many cases the adoption of corrstitutional formulze utterly at variance with chemical facts.Without discussing the meaning of the somewhat vague word “colour,” it may be pointed out that the colour of a substance depends, amongst other conditions, on its crystalline structure. In the course of some work carried out with Mr. Revis, it was noticed that isonitrosohydriiidone forms a yellow sodium derivative, the colour of which depends on the temperature at which it is crystal-lised ; when heated at 70--80”, the yellow salt is rapidly converted into a, scarlet modification, owing to a, change in crystalline form taking place. Numerous examples of a similar kind are known, and taking this fact into consideration, and having regard more especially to the number of undoubted exceptions to Dr.Armstrong’s colour rule, it is impossible to accept his generalisation in its present form. Mr. LINGagreed in considering that the quinone theory was not established as a general rule. Dr. ARMSTRONGthought tbat Mr. Green’s generalisation was of considerable value as a working hypothesis, but he was inclined to doubt whether it would be possible by means of such a test as that suggested to sharply divide dye-stuffs into two classes; it was rather to be expected that the members of the two classes would merge gradually into each other.As the method would in many cases incite the farther investigation of structure, which was so much to be desired, it must prove to be of considerable service. As to the alternative formuls suggested by Mi-. Green, he could not regard them as satisfactory on the whole; the representation of oxygen as R tetrad in such a case as that of Meldola’s blue, for example, a,ppeared to him to involve conclusions beyond the bounds of probability. Mr. Green had spoken of the Armstrong-Nietzki quinonoid theory of colour : unaccustomed as he was to put forward claims of priorit,y, he could not help remarking that althongh Nietzki had undoubtedly called attention to the occurrence of quinonoid structure in many colouring matters, he had iiever attempted to generalise.He, the speaker, had, however, endeavoured to extend the hypothesis not only to colouring matters, but to coloured sub- stances generally, and had given a definition of the term quinonoid, which included even snbstaiices such as iodoform. No doubt the difficulties to be overcome were very great, and it would be long before we should be able to explain all cases of the occurrence of colour ; meanwhile all me could do was to patiently investigate the facts. BIr. GREEK,in rep’y, wished it to be undel-atood that he regarded 229 the quinone theory as affording a satisfactory explanation of the colour of organic dye-stuffs, though not of tLc colour of all coloured organic compounds. "157. "Derivatives of a-hydrindone." By C.Revis and F. StanleyHipping, Ph.D., D.Sc. As a-hydrindone and camphor are in some respects analogous in constitution (inasmuch as each contains two closed carbon chains, in one of which occurs the group -CH,*CO-), the behaviour of the two ketones and of corresponding derivatives has been studied, in order to ascertain to what extent they would show analogous reactions ;it has thus been found that except in a few instances there is a marked difference in chemical behaviour. a-Hydrindoneoxime, for example, behaves quite unlike camphor- osime when heated with mineral acids, as it yields the two condensa- Lion products (anhydrobishydrindone and truxene) which are pro-duced from hydrindone itself (Kipping, Trans., 1894, 65, 489). Monobromohydrindone, unlike a-bromocamphor, is readily acted on by alcoholic potash, giving a coiideiisation product of the composition C,,H,313r0z(Proc., 1895: 10, 157).Dibromohydrindone resembles a-dibromocamphor in withstanding the actioc of nitric acid, but it differs from the camphor derivative in being readily acted on by nlcoholic potash, giving a condensation product of the composition C,,Hl,Br02 ; this substance crystallises from benzene in flat prisms, wlrich contain one molecule of benzene, and melts at about 150', also decomposing. A somewhat similar condensation product is obtained by treating dibromohydrindone with an alcoholic solution of sodium ethoxide ;this compound crystallises in prisms melting and decom- posing at 173-1 74O,and probably has the composition C1,H,,OZBr-OEt.Attempts to prepare hydrindene, C91Tlo,by first reducing hydrin- cloneoxime to the primary arnine, CgHg*NH2, and then converting the base into the hydrocarbon by the ordinary methods, were not more successful than those previously made by Konig (Inaug. Diss., Leipzig, lS89), owing to the production of resinous compounds in the various stages of the process. Benzoylaminohyd&d ene, CgHg.NH*COPh, prepared from the base, crystallises in colourless needles, and melts at 142-143'. Benzylideneaminohydrindene, C9Hg*N:CHPh, the condensation pro-duct of bsnzaldehyde and aminohydrindene, forms transparent prisms, melting at 74-75', An2imJydrindene oxalate crystallises in clusters of white, opaque prisms, and is rather sparingly soluble in cold methyl alcohol and in cold water.Hydrindone semicarbaxide, C9H8:N*CO*NX*NH2,separates from 230 dilute acetic acid in prisms, which contain 7 mols. of water ; it melts and decomposes at about 239". "158. "Not~son nitration." By Henry E. Armstrong. In previous notes on nitration (Proc., 1891, 7, 87-91), E. C. Rossiter and the author have drawn attention to the part played by keto-compounds, and to the explanation which their formation, as well as that of other addition compounds, affords of the production of secondary products in nitrations. Attention is now drawn to the conditions to be observed in pi+ paring normal products of nitration. However carefully ,%naphthol be subjected to tfhe action of liitric acid, a considerable proportion of resin is always formed, e~em wheu the product is subjected to the action of reducing agents ; but if bromo-p-naphthol be used instead, the formation of resin may be entirely avoided, a practically theo- retical yield of 1: 2-nitro-P-naphthol being obtained.Obviously, in the latter case, the addition compound which is first formed, and also the keto-compound derived from it, are far less sensitive to the action of the unchanged naphthol, so that the interaction affording the resin is prevented from occurring. Moreo~-e~,although a, nitro-keto-compound, such as is represented by the forinnla H*NOB ('()O , \/\& would not be converted by reduction into nitronaphthol, it is to he expected that if bromine occupied the place of the hydrogen, it would be readilyremovable. Not only is this actually the case, but nothing more powerful than a sulphitc is needed; yet, in some instances, it is necessary to use a stronger reducing agent: thus, the componods CleN02 CI-NO2 /\A0 /\/LO Br! 1 I and 1 I ic1 are unaffected by sulphite, but as \/\/ v\/experiments made by Mr.E. Rich show, they are at once converted into the corresponding nitronaphthols by means of hydrogen iodide, *159. "3-Bromo-B-naphthol." By Henry E. Armstrong and W.A. Davis. At present, the only bronio-/?-naphthol known is the 1 : 2-modificn-tion, which is the sole product of the direct interaction of brominc and the naphthol ; indirect inethodv capable of aff ording isomeric forms are much needed.The authors 1ini.e succeeded in devising EL method of convertiiig 1:3'-dibromo-/3-nnphthol into 3'-bii0m0-/3- naphthol by removing the bromine atom in position 1; this consists in digesting the dibromo-compound with a saturated solution of hydrogen iodide, ultimately at a temperature not exceeding 65'. If' care be taken, the yield is that indicated by theory; but if the naphthol be allowed to dissolve in the acid solution, and the tempera- ture to rise too high, an intractable condensation product is alone obtained. 3'-Bronio-p-naphthol crjstallises fi om benzene iii colourless needles melting at Ui'; the acetate derived from it melts at 103'. On sulphonation bp means of cold sulphuric acid, it yields a some-what nustable monosulphonic acid, which is converted into 1: 3'-di-bromo-@naphthol by bromine, and into l-nitro-3'-bromo-p-naphthol by nitric acid ; doubtless, therefore, sulphonation takes place in position 1.By heating the bromonaphthol with excess of snlphuric acid at loo', a stable disulphonic acid is produced. The behaviour of higher brominated derivatires of ,%naphthol and of the bromo-a-naphthols with hydrogen iodide will be considered in a subsequent communication. "160. Derivatives of nitro-@-naphthols.' By W.A. Davis.'L The difficulties which attend the nitration of P-naphthol do not affect that of its ethers, which shorn no tendency to give keto-corn- pounds ; moreover, the uitromethoxy- and nitrethoxy-naphthalenes are all more or less intensely coloured substances, whereas the corre- sponding phenol derivatives are colourless : hence the investigation of these compounds is of importance from several points of view.Besides repeating and confirming Gaess's observations on the nitration of /3-ethoxynaphthalene (J. pr. Chenz., [a], 43), the author has prepared the me thoxy-compounds corresponding to those described by Gaess, and has subjected both series to crystallographic examina- tion. 1: 2-Nitromethoxynapbthalene (rn. p. 126') is the main product when nitratiou is effected in acetic acid solution at a temperature not exceeding 1.5'; it forms 90 per cent. of the total product, and is accompanied by about 1per cent, of the 1': 2-nitromethoxy- (m.p. 69') and about 3 per cent. of the 3' : 2-nitromethoxy-compound (m. p. 134'). The amido-derivatives were prepared by reducing the nitro-corn- pounds with tin and hydrochloric acid. 1:2-nmidomethoxynaph-thalene melts at 84', and its acetyl derivative at 175'; the 3' : 2-amido-compound melts at YS', and its acetyl derivative at 183O, whilst 1' : 2-acetamidomethoxynaphthalene melts at 145'. The action of a molecular proportion of bromine on 1: ?-nitro- 232 ethoxynaphthalene gave 3' : 1: 2-bromonitrethoxynaplitltaleiie (m. p. 141'), the structure of which was determined by its formation on ethylat.ing 3' : 1: 2-bromonitronaphthol. When hydrolysed by alco- holic potash, it yields 3' : 1: 2-bromonitronaphthol (m.p. 122'). If any excess of bromine be used in the bromination, dibrom- ethoxynaphthalene (m. p. 94') and tribroniethoxynaphthalene (m. p. 128') are formed by tbe displacement of the NOz group by bromine. 3' : 1: 2-Bromamidoethoxynaphthalencmelts at 84", and its acetyl derirative at 246'. 3' : 1:2-Bromonitromethoxynaphthalene, prepared by bromi nating 1: 2-nitrornethoxynaphthalene, melts at 152' ; the corresponding amido-compound melts at 73', and its acetyl derivative at 252". 3' : 1 : %Bromonitronaphthglamine, obtained by heating 3' : 1:2-bromonitrethoxy-or methoxynaphthalene with alcoholic ammonia at 160°, is a yellow, crystalline substance, melting at 190". On nitrating 1: 2-nitromethoxpaphthalene with concentrated acid (d 1-42> at O', a mixture of 1: 3' : 2- and 1: 1' : 2-dinitro-methoxynaphthalenes was obtained ; these were separated only with difficulty.1: 3' : 2-Dinitromethoxynaphthalene was, however, ob- tained in a pure state by nitrat,ing 1:3'-nitromethoxynaphthaleneat 0". It melts at 198'. The 1:1':2-dinitro-compound melting at 190' was obtained by similarly nitrating 1: 1'-nitrornethoxynaphthalenc. The structure of these two dinitro-compounds was determined by converting tliem into the corresponding dini tronaphthylamines, which had been previously prepared and described by Gaess (Zoc. cit.). 1 : 2-Nitromethoxyx1aphthalene, on being heated with alcoholic potash, easily yields 1: 2-nitronaphthol ; on being heated with alco- holic ammonia at 160°, it is converted into 1: 2-nitronaphthylamine.It is noteworthy that, under similar conditions, 1: 2-nitronaphth~l yields scarcely any nitrcinaphthylamine, a large amount of resin being formed . SOzClZis apparently without action on 1: 2-nitrethoxy-or nitro-rnethoxynaphthalene ; it acts, however, veq- readily on 1: 2-acet-amidomethoxynaphthalene, giving a, beautifully crystalline mono-chloro-derivative, melting at 167". The struc!,ure of this has not yet been determined. In order to determine whether /%ethoxy-z-naph- chylaminc resembles p-1;aph tho1 or a-napht hylamine, the behaviour of its acetyl compound with bromine was studied ; the action was carried out at 0". 3' : 1 : 2-Bromacetamidoethoxynaphthalene, in. 1). 245", was obtained as sole product.Thus its behaviour is simply that of a derivative of P-naphthol in which position 1 is occupied? the NHAc group, apparently, being without influence ; this is of especial interest, as, according to a private communication from Professor 233 Xietzki to Professor Armstrong, its behaviour towards nitric acid is comparable with that of a-acetnaphthalide. The behaviour of bromine with p-methoxy-a-acetnaphthalideis the same as towards the ethoxy-compound, 3' : 1: 2-bromomethoxyacet-naphthalide (m. p. 252') being obtained, '161. '' Morphotropic relations of s-naphthol derivatives." By W. A. Davis, Although the crystallographic relationships of benzene derivatives have been very fully investigated, little work of a similar character 11x7 been hitherto carried out upon naphthalene compounds, and only one morphotropic series of derivatives has been recognised, viz., that afforded by the chloro- and bromo-naphthalenetetrachlorides, which has been discussed by Hintze (Pogg. Ann., 1874,6,177).The author has examined the compounds referred to in the previous note, and finds the following crystallographic constants. Substance. 1 System. ' Geometrical constants. I 1 /3 = ;GI" 26' 1 : 2-Nitretlioxyn~phtlialene,. . , . . . . . . Orthorhombic 2 -4897 : 1: 1*1606 1 : 2-Nitromethoxynaplithalene . ... .... Anorthic 0-9382 : 1: 1-2088 a = 97"45') /3 = 92" a',I I y = 88"27+' 1 : 2-Nitrobenzjlnnphthol (Sayer) .... . . Orthorhombic 0 -4892 : 1: 1.0632 1 : 2-Acetamidomethoxynsphtlialene ... ' Nonosymmetric 0"7999 : 1: 0 .'is11 @ = 99" 21' 1 : 3' : 2-Nitrobrometlioxynaphthalene . j Anorthic 1'4274 : 1: 1*0265 a =95'0', B = 109'18', y = SO" 15' ? : 1: 1'1526 The crystallographic data thus obtained afford a series presenting the following salient points : (1) In the transitiods from 1:2-nitronaphthol to its methyl, ethyl and benzyl ethers, although marked changes of symmetry occur, the axial ratio c : b remains nearly constant. In the passage from nitro-+naphthol (monosymmetric) to its methyl ether (anorthic), there is a degradation of symmetry ; but an increase in symmetry occurs in passing from 1: 2-nitronaphthol to its ethyl ether (orthorhombic). These changes of symmetry are analogous to those which occur in the benzene series in passing from acetanilide to methyl and ethyl acetanilide respectively, only in the latter cases the changes are not brought into evidence by changes of system, but only by correspond-ing changes in the axial ratios. (2) When 1:2-nitrethoxynaphthalene (orthorhombic) is changed by the introduction of a bromine atom into position 3', a degradation to anorthic symmetry takes place, the axial ratio c :b remaining,.however, nearly unaffected. (3) A remarkable increase of symmetry occiirs when 1:2-nitro-inethoxynaphthalene (anorthic) is converted into the 1 : 3' : 2 dinitromethylether (orthorhombic), whilst the ratio of the c and b axes remains nearly constant ; this increase of symmetry accompany- ing the introduction of successive units of the same radicle is com-parable with the change in symmetry that occurs in the benzene series in passing from paranitrophenol (monosymmetric) to di-nitro-and trinitro-phenol, both of which are orthorhoinbic, tha symmetry in the case of the trinitro-compound tending towards that of the tetmgonal system.When the various nitro-derivatives are melted on a microscope slide, and the solidified films are examined between crossed nicols, in the manner recently suggested by Mr. Pope (Proc. 1896,12,142) the appearances t'ltey present are very character- istic, as the photographs which arc exhibited show ;and an important proof is thus given of the use to which such a method can be put either in identifyiiig isomeric substances occurring together-par- ticularly if these melt at nearly the same temperature and are, therefore, liable to be confused with one another-or in recognizing the occurrence of a change from one crystalline modification to anoth e 1"."162. "Researches on tertiary benzenoid amines." 11. By Clare de Brereton Evans, B,Sc. In continuation of the experiments referred to in a previous abstract (cf. Proc., 1896, 12, 235), the behaviour of diethylaniline, as well as that of dimethylortho- and dimethylpara-t oluidine, has been further studied, and the series of isomeric dimethylanilinesalphonic acids has been completed by the preparation of the ortho-compound. For purposes of comparison, methyl- and ethjl-aniline have also been subjected to sulphonation.Dimethylanilineorthosulphonic acid was prepared by methylating parabromanilineorthosulphonic acid and subsequently reducing the product. The constitution of the acids dmived from thc t,oluidines was determined by niethylating the sulphonic acids of toluidine of known constitution. Summarising the facts, the stliking conclusion has been estab- lished that whereas orthosulphoiiic acids are readily obtained froni 235 aniline derivatives-for example, parabromaniline, meta-acids only are formed from dimethyl- and die thyl-aniline and dimethylpara-toluidine : there being, apparently, ail extraordinary “aversion ” on the part of the sulphonic radicle to take up the ortho-position relatively to the NR’, group.A similar inhibiting influence appears to be exercised by the group. in preventing the entry of more than one bromine atom into the ortho-position. Such being the case, it is the more remarkable that when the sulpho-group does become displaced iiromination extends much further in the case of the tertiary arnines :dimethylaniline-parn and ortho-sulphonic acids being converted into tetrubromodimeth yl -aniline and diethylanilineparasulphonic acid even into pextabroino- diethylaniline ; 1:2 :5-dimethylortliotoluidinenietasulphonicacid in like manner yields tetrabromodimethylorthotoluidine. Sulphanilic acid, it is well known, yields only tribromaniline. In the case of the acids derived from the dimethyltoluidines, viz., \/S03H I. 11.111. of wbicli No. 111 was prepayed by methylatirig the toluidinesulph- onic acid, only the first yields a perbromide. It is noteworthy that the ~ulphochlo~~ides of the various acids are all hydrolysed with somewhat unusual readiness. Methyl- and ethyl-aniline are found to behave exactly as aniline, so that the presence of hydrogen in association with the nitrogen at,um would appear to play a part in the formation of ort11amido-d e rivu-tives. It is proposed to extend the experiments to the dirnethylxylicliiics and cumidines. 163. “On the circumstances which affect the ratio of solution of zinc in dilute acids, with especial reference to the infiuence of dissolved metallic salts.” By John Ball, A.R.S.M. The author considers the effects 011 the rate of solution of zinc in dilute acids of (i) variations of concentration of the acid; (iij pre-vious special treatment of the acid ; (iii) variations of temperature ; (iv) variations of pressure ; (v) variatioris of the surface condition of the zinc; (vi) alloys of known amounts of foreign metals with the zinc ; (vii) performance of the solution in vessels of different mate- i*ials; (viii) addition to the acid solution of (u) oxidising agents ; (b) reducing agents ; (c) foreign &=ids; (d) salts of foreign metals.The main portion of the paper deals wihh the effects produced by the presence of salts of various metals in the solution. Two main serics of quantitative experinients for the comparison of the relative effects of salts of the different metals are described: one in sola-tions of sulphuric acid with magnesium, aluminium, chroniiiim, manganese, iron, silver, copper, cobalt, or nickel sulphates as added salts; and one in solutions of hydrochloric acid, with manganese, lead, tin, copper, cobalt, gold, platinum, or nickel chlorides added.There is also a separate set of experiments in sulphuric acid solu-tions, with cobalt sulphate as added salt, in order to determine quantitatively the influence of the amount of salt, used. The metal used was pure distilled zinc, specially cast in very thin sheet. The results show that, both with sulphuric and hydrochloric acids, the addition of the foreign salts always accelerates the reaction, except in the case of magnesium and aluminium salts, which seem to be uearly without influence.The accelerating effect is most felt at the beginning of the reaction, and the velocity soon reaches a maximum (higher than that which would hold if no salt were present), which is practically constant nearly to the end. The acceleration is shown to be governed by a number of causes, of which the amount of metal precipitated from the added salt on the zinc is only a subordinate one, as the acceleration is often very great in cases where no precipitation can be determined---e.g., 0.080 gram of nickel as sulphate added to a mixture of 17 C.C. of water, with 8 C.C. of sulphuric acid, at a temperature of 40°, increased the maximum yelocity of reaction with zinc 37.87 times.In these cases a very minute trace of the added salt exerts an enormous influence, and, as shown by tho experiments with cobalt sulphate, the effect of adding inore of the salt becomes less perceptible as the total amouut is increased, and ultimately we reach a point where further addition is without influence. 164. “The oxidation of ferrous sulphate by sea-water, and on the detection of gold in sea-water.” By E. Sonstadt. The experiments now described were made in the autumn of 1895, .on sea-water supplied by the Great Eastern Railway Company in oak kegs, freshly filled, the water being stored in glass bottles as soon as received, and filtered before use. I. On the Oxidation of Ferrous Szclphate by Sea-water.-In 1872 (Chem. News,25, 196, 231, and 241), the author gave a description of experiments proving the existence in sea-water of calcium iodate, four parts of this salt being shown to be presentl in one million parts sf sea-water.As these experiments have not, within niy knowledge, been repeated, and as I do not know of any anal)-sis of sea-water 237 recognising the presence of any salt therein capable of acting as an oxidiser, it seemed desirable to make direct experiment on the oxidis- ing power of sea-water. To do this satisfactorily, it seemed neces- sary to compare sea-water against sea-water so treated as to reduce any salts of the nature of iodates that it might contain, due care being taken to thoroughly aerate the treated portion. First Experirfienf.-l.$ lbs.sea-water were evaporated to dryness with a small quantity (about 2 grams) of pure mercury, and the residue was heated in a porcelain crucible into which a current of hydrogen was passed, until the mercury was completely expelled. The salts were digested in water, and the solution made up by wash- ings to the original quantity. The solution was then put into a Winchester quart bottle, and repeatedly shaken up, the air being renewed from time to time. When it was judged that the aeration was complete, one pint of the solution was put into a bottle which it nearly filled, and 1gram of crystallised ferrous sulphate was added. A pint of the original sea-water was put into another similar bot,tlc, with the same quantity of ferrous sulphate, and 14 C.C.of dilute hjdro-chloric acid was added to each solntion. The bottles were corked, and after sufficient shaking to ensure mixture, were set side by side for tbree days, when the contents of both bottles were filtered simul- taneously. After washing the precipitates with equal quantities of water, drying, and ignition, the ferric oxide from the natural sea-water weighed 0.0182 gram, and that from the treated sea-water., 0.0132 gram. Secod Experinzent.-Tbis was conducted similarly to the first experiment, except that instead of evaporating the sea-water with mercury, the latter was rubbed up with the residue left after drying, the subsequent heating in a current of hydrogen being conducted as before. Also, no acid was added to either the natural or the treated sea-water, and after the addition of ferrous sulphate, the solutions were allowed to stand in the corked bottles for 13 days before filter- ing.The natural sea-water gave ferric oxide 0.0540 gram (after solution and reprecipitation 0.0528 gram), and the treated sea-water 0.0270 gram. Thus, the differsnce in this case, when no acid was added, and more time was allowed for the formation of the precipi- tates, was very much more than in the first experiment, and is greably in excess of what can be due to the influence of the iodate present in the untreated sea-water. Although in these experiments it was found impossible to com-pletely dissolve the salts obtained after ignition, in the quantity of water required to form an equal volume with the original sea-water taken, yet there is no reasonable ground for supposing that the change in composition thus effected could sensibly aflect the oxidising 238 power, apart fi=om the reduction involved of the iodate, and other salts at present unrecognised, of it reducible character.The in- soluble residue contained traces of several metals, all of which were not definitely recognised, an account of which I defer until an opportunity occurs to me of working upon larger quantities of material. 11. Oit the Detection of Gold ia Sea-TVuter by means of iUe~-cwy.-About 20 grams of pure mercury was agitated in a flask with about half a gallon of sea-water for a long while, the flask being placed at interrals on a water bath, so that the liquid became warm, though not hot.In subsequent experiments the water was not warmed, and no special proportion of mercury was used, though obviously, the smaller the proportion of mercury, the more agitation would be necessary to obtaiii the same result. The mercury was separated, washed, and dried with bibulous paper. The mercurr was then dtltilised in a porcelain crucible having an uninjured internal sur-face. A black, adherent film remained, fixed at a red heat. When the crucible had cooled, a small quantity of strong hydrochloric acid was added, which, 011 warming, dissolved the greater part of the film, leaving, however, a stain not removable by repeated similar treat- ments. The acid solut,ion being washed away, and the crucible dried, a drop or two of aqua regia was let fall on the stain, which was almost immediately dissolved. By cupellation, a very minute gold bead was obtained.In some experiments, the mercary that had been agitated with sea- water was distilled in a current of hydrogen, but on afterwards heating the black residue in t,he porcelain boat in the open air, the residue was not adherent, and could not therefore be treated as described. To obtain an adherent, fiim, 4to 5 grams .of mercury must be left for volatilisation in the open. The mercury that is distilled off in a current of hydrogen is quite pure ; but that volatilised in contact with air is not pure ; for if a portion of it be condensed on a cool surface, and then volatilised, a residue remains which disappears on strong heating.Silver is one of the metals dis-solved out from the black residue by the hydrochloric acid with which it is treated. This fact, although somewhat outside the sub- ject of the present piper, is worth mentioning, as having a bearing upon the question as to the condition in which the precious metals are present in sea-water. Mercury does not decompose silver chloride, either in the wet or dry way ; and yet it separates silver from sea-water. The most natural inference appears to be that the silver salt in sea-water is so far attenuated by dilution as to have under- gone molecular disruption, so that it may be considered to be present as metallic silver in solution. If this be so in respect to silver, the gold in sea-water is probably also in a similar condition.239 A comparison cannot be instituted between the simple and easy process now described, for detecting the presence of gold in sea-water, and the processes given in tho author's paper '' On the Presence 'of Gold in Sea-water " in 1872 (Chem. News.,26,159), because the sea-water that comes in kegs from the sea-side is very much poorer in gold than the water of the Irish Sea, on which the author's earlier experiments were made When some gallons of sea-water, furnished by the Great Eastern Railway Company, were heated with ferrous sulphste and a little hydrochloric acid, and the precipitate, after a few days, collected, the minute gold bead from this precipitate (which was lost by accident before it could be weighed) was certainly but a small fraction of what the same quantity oE sea-water previously experimented upon would have yielded.Whe t'her this poverty in gold of the keg-water is due to its brieE contact with wood, or to the circumstance that it is taken from shallow water near tie shore, where a certain admixture with mud or clay is inevitable, may be doubtful. But it is probable that finely divided clay, mixed with sea-water, would carry down with it, in settling, most of tbe gold present. ADDITIONS TO THE LIBRARY. I. By Pzwchase. Blyth, A. Wynter. Foods : Their Composition and Analysis. A manual for the use of analytical chemists and others. Wit,h an Introductory Essay on the history of adulterakion.Fourth edition, revised and enlarged. xxxii + 735 pp. London 1896. Dammer, 0. Handbuch der Anorgaiiischen Chemie. Bde. I, 11,1, IT, 2, and 111. 1892-1894. Stuttgart. Circulating copy. Gautier, Armand. Les Toxines microbiennes et animales. Avec 20 figures dans le texte. vii+617 pp. 8vo. Paris 1896. LBger, E. Les Alcalo'ides des Quinquinas. Avec une Preface de 31. E. Jungfleisch. viii +278 pp. 8vo. Paris 1896. Lorenz, Hans. TJ euere Kiihlmaschinen, ihre Konstrnbtion, Wir- kungsweise und industrielle Verwendung. viii +219 pp. Miinchefi 1896. Meyer, Arthur. Untersuchungen iiher die Starkelcorner. Wesen-u. Lebensgeschich te der Starkekorner der hoheren Pflanzen. Mit 9 Tafeln u. 99 in den Text gedruckten Abbildungen. xvi+318 pp.Jena 1895. Minervtt. Jahrbuch der gelehrten Welt. Sechster Jahrgang. 1896-1897. xxiv +1082 pp. St'rassburg 1897. 240 Rosenbusch, H. Mikroskopische Physiographie der Mineralien und Gesteine. Band 11. xiv+ 1360 pp. Stuttgart 1896. Schnabel, Carl. EIandbnch der Metallhuttenkunde. Zweiter Band. Zink, Cadmium, Quecksilber, &c. xii + 760 pp. Berlin 1896.. Schultz, Gustav, und Julius, Paul. Tabellarische Uebersicht der im Haridel befindlichen kunstlichen organischen Farbstoffe. Dritt>e vollstandig umgearbeitete und stark vermehrte Auflage. xvi + 216 pp. Berlin 1897. 11. Donations. The Edinburgh Philosophical Journal. Vols. 1-10. 1819-1824-From Professor W. 11. Dunstan, F.R.S. Jahresbericht uber die Fortschritte der Chemie und verwandter Theile anderer Wissenschaften.I & I1 Heft. 1886. From Professor W. R. Dunstan, F.R.S. Harcoprt, A. G. Vernon, and Madan, H. G. Exercises in Practical Chemistry. Fifth edition revised by R. G. Madan, M.A., F.C.S.. xvi+598 pp. Oxford 1897. From H. G. Madan, Esq. Watt, George. A Dictionary of the Economic Products of India. Index. 165 pp. Calcutta 1896. From the Government of India. Pumph1et. Jowett, H. A. D. On Atisine, the Alkaloid of Aconitum Hetero- phyllum. 30 pp. London 1896. From the Author.. At the next meeting, Thursday, December 17, the following papers. mill be received :-“ On the experimental methods employed in the examination o.f the products of starch hyd~olysia.” By Horace T. Brown, F.R.S., G. H. Morris, Ph.D., and W. H. Millar. “ On the specific rotation of maltose and of solnble starch.” I$-Horace T. Brown, F.R.S., G. H. Morris, Ph.D., and W. H. &War. “ On the relation of the specific rotatory and cupric reducing. powers of the products of starch hydrolysis by diastase. Ry Hiorace-T. Brown, F.R.S., G. H. Morrig, Ph.D., and W. H. Millar. “Percarbonate of Cobalt.” By R. G. Durrant.
ISSN:0369-8718
DOI:10.1039/PL8961200225
出版商:RSC
年代:1896
数据来源: RSC
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