摘要:

THE QU ART E R LY JOURNAL OF THE CHEMICAL SOCIETY OF LONDON. W DE LA RUE PH.D. F.R.S. A W. HOFHANN LL.D. F.R.S. E.FRANKLAND PH,D. F,R,Se I W,A+ MILLER MDI F*R.S* LONDON HIPPOLYTE BAILLIERE 219 REGENT STREET AND 440 BROADWAY NEW PORK U.S. PARIS J. B. BAILLIERE RUE HAUTEFEUILLE MADRID BAILSY BAILLIERE CALLB DEli PBINCIPE. 1860. LONDON ! PXINTEU BY BhBRISON AND SONS O~T.~it~I”8 LANE w.0. CONTENTS OF THE TWELFTH VOLUME. PAGE On the Action of Bromine on Bromacetic Acid. By W. H:Perkin F.C.S. and B. F. Duppa Esq. $c. ............................................................................... 1 On some Minerals containing Arsenic and Sulphur from Chili. By Frederick Field ,..................................................,...............................................................8 On Titanic Acid. By E. Riley F.C.B..................................................................... 13 On the Constitution of Lactic Acid. By Dr. H. Kolbe ................................ ........ 15 Conversion of Lactic Acid into Propionic Acid By Dr. C. Ulrich .................... 23 On some Native Combinations of Oxide of Mercury with Oxide of Antimony. By Frederick Field ............................................................................................ 27 On a New Method for the Quantitative Estimation of Nitric Acid. By Dr. E. Pugh ............................................. ...............................................................,....35 New Volatile Organic Acids of the Mountain Ash Berry. By A. W. Hofmann 43 Analysis of the Water of Holywell North Wales. By James Barrat ................ 52 Discourse :-On the Composition of the Animal Portion of our Food and on its Relations to Bread. By J. H. Gilbert Ph.D.,F.C.S. .......,.....,.,............ 54 Analysis of the Water of a Spring at Billingborough Lincolnshire. By J. W. Kynaston .... ... ........................................,......................................,................ 57 Chemical Society of London. By Professor Hoffmann ............................... 62 On some Derivatives from the Olefines. By Frederick Guthrie Ph.D. ......,,.... 109 Note on Paviin. By G. G.Stokes Sec. R.S. ...... ........ ...........,..............,,...........126 On the Absorption of Hydrochloric Acid and Ammonia in Water. By Henry On Ammonia and its Derivatives. Discourse delivered to the Members of the E. Roscoe and William Dittmar ... .............,....,................................................ 128 iv CONTENTS. PAGE On Rases produced by Nitrous Substitution . By C . S. Wood ........................... 152 On the Action of Hydrochloric Acid upon Sulphide of Mercury in the presence of certain other substances . By Frederick Field ........................................ 158 On the Action of Boracic Acid upon the Salts of the more Volatile Acids at High Temperatures . By A . Norman Tate .................................................... 160 Anniversary Meeting of the Chemical Society ........................................................166 On the Action of Boracic Acid upon the Carbonates of the Alkalies and Alkaline Earths . By Charles L. Bloxam ................................................... 177 On the Colouring Matter of Madder. By Edward Schunck Ph.D. F.R.S. F.C.S. ................................................................................................................198 On the Polyatomic Alcohols . A Discourse delivered before the Fellows of the Chemical Society of London. By Dr . H.Debus F.C.S. ............................ 222 Action of Metals upon Iodide of Ethylene C4H41f By Carl Von Thann and 258 J. A Waiiklyn ....................................................................................................Researches on the Atomic Weight of Graphite. By B. C.Brodie F.R.S......... 261 On the Combination of Carbonic Oxide with Potassium . By 13. C. Brodie F.R.S. ........................................................................................................ 269 Decomposition of Gaseous Compounds by Electrical Incandescences. By Henry Buff and A . W.Hofmann....................................................................273 Proceedings at the Meeting8 of the Chemical Society ......................................... 290 Titles of Chemical Papers in British and Foreign Journals ............................. 297 Index................................................................................................................ 393

ISSN:1743-6893    

DOI:10.1039/QJ86012FP001

出版商:RSC    

年代:1860

数据来源: RSC

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8 11.-On some Minerals containing Arsenic and Sulphur from Chili. BY FREDERICK FIELD. Arsenic and Silver.-A remarkable instance of the oxidation of arsenic when in combination with copper appears in the mineral Condurrite examined by Professors Faraday and Blyth. In the northern part of Chile where little or no rain falls and the mines have only been recently worked many minerals in a highly oxidized state are found which have been preserved untouched from the absence of any solvent. Arsenic is obtained sometimes as arse-nious acid and sulphur as sulpliuric acid in combination with the oxides of iron and copper. In Peru even crystals of native sulphate of silver have been observed. From a mine in the imme- diate neighbourhood of Copiapo I received some specimens of a mineral consisting apparently of native arsenic having a specific gravity of 5.75 breaking easily under the hammer with a fine granular fracture and presenting an iron grey colour vhen broken.It could be reduced to the finest powder by trituration. Analysis gave the following results in 100 parts :-Arsenic . . 79.21 Silver . 12.56 Cobalt . . 3.24 -95.01 No sulphur could be detected and other metallic elements were sought for without success. Many analyses gave more or less the same results always leaving a loss of nearly 5 per cent. rt occurred to me that a considerable portion of the arsenic might exist in an oxidized state ; and this seemed the more probable on account of the low specific gravity of the mineral (the same as that of metallic arsenic) while it contained so large a percentage of silver.On digesting some of the pulverized compound in w-arm water for a few hours the liquid after filtration was decidedly acid to test paper ; and on the introduction of a few drops of hydrochloric acid and the passage of a current of sulphuretted hydrogen a very bulky precipitate of sulphide of arsenic was produced that arsenious and not wrsenic acid was present was evident from the immediate precipitation of the sulphide. 30.00 grs. of the mineral digested for twentyfour hours in ten ounces of water kept at a temperature of about 150' Fahr, lost 5-15 grs. in weight and the filtered solution yielded 6-42of sulphide of arsenic. Before the passage of the sulphuretted hydrogen the filtrate was acidulated with hydrochloric acid and the precipitate was of a pure canary yellow.After standing many hours the sulphide was separated by filtration; a few drops of sulphide of ammonium caused a brownish-black colour when added to the filtrate which deposited slight flakes after some time of what proved to be sulphide of cobalt. Although arsenite of cobalt is insoluble in water it becomes slightly soluble when digested in solution of arsenious acid sufficiently so at leaat to give a reaction with alkaline sulphides. This accounts for the trace of cobalt found in the liquid. The composition of' the mineral appears to be as follows :-Arsenic . . 66-17 Arsenious acid . . 17.22 Silver . 12.56 Cobalt .. 3.24 Oxide of cobalt . . traces M. Domeyko to whom I sent a specimen of this mineral having examined it through a very strong lens imagines that the silver is mechanically mixed in a very minute state of division through the mass of arsenic arsenious acid and arsenide of cobalt. Sulphide of Copper and Arsenic.-I am not aware that any simple natural combinations of arsenic sulphur and copper have hitherto been discovered. The mineral tennantite although its analysis differs aomewlmt in the hands of various chemists always contains iron aid the many varieties of fahlore generally have in addition to this element more or less antimony zinc arid silver. FIELD ON SOME MINERALS The following are some analyses of tennantite :-(1.) Phillips.(2.) Kudernatsch. (3.) Fearnley Copper . . 47.70 48-94 42.60 Arsenic. . 12.46 19.10 19.01 Sulphur . 30.25 27.76 29.18 Iron . . 9.75 3.57 9.21 100.16 99.37 100*00 I have obtained lately from quite a newly discovered mine in the Cordilleras of the Andes splendid specimens of a mineral consisting essentially of arsenic copper and sulphur with mere traces of iron and silver. The mineral occurs in highly crystal- line black masses covered with layers of cyanose (sulphate of copper) and having a specific gravity of 4.39 hardness about 3.8. The mean of several analyses gave the following composition:- Copper . . 48-56 Sulphur . . 31-80 Arsenic . . 19.10 Iron . . -42 Silver . traces. probably having thc formukt 3Cu,S . ASS, which requires- Copper .. 48.60 Sulphur . . 32.42 Arsenic . . 18-98 100*00 and may be considered its a tribasic sul'pharseniate of copper corresponding to the tribasic sulpharseniate of potassium if we admit that Cu replaces the K as it does Ag in many minerals. I have proposed the name guayacanite for this mineral as it was first brought from the mine to the large copper-smelting works of Guayacan in Chili. Guayacanite may be considered as tciiriantitc in which the iron is rcplaccd by arsenic :- CONTAINING ARSENIC AND SULPHUR. 11 Guayscanite. Tennantite. Copper . 48.56 47.70 Sulphur . . 31.80 30.25 Arsenic . . 19-30 12-46 Iroii . . 42 9.75 c_- -__. 99.88 100*16 Pursuing researches upon the arsenical minerals which occur from time to time owing to the rapid development of mineral wealth in this quarter of the globe I examined a small iron-grey coloured metallic vein traversing a larger one of blue carbonate of copper.This mineral mas obtained from a mine about twenty- five leagues south-east of Coquimbo. It was very difficult to free the mineral from adherent particles of carbonate of copper &c. but a great portion was removed by digestion in acetic acid and when thus purified gave- Copper . . 35.82 Sulphur . . 17.91 Arsenic . . 14.20 Residue and Oxide of Iron. . 28.24 96.17 There mere also traces of antimony zinc and silver and probably some carbonate of lime which was not estimated as the object was principally to learn the relative proportions of copper arsenic and sulphur which were found to stand to one another in 100pts.as under :-Copper . . 52.73 Sulphur . . 26.36 Arsenic . . 20.91 100~00 Or 3Cu,S ASS, which formula requires- Copper . . 52-89 Sulphur . . 26.44 Arsenic . . 20.67 100.00 FIELI) ON SOJIE MINERALS ETC. This may be corisidercd as a tribasic suijhrsenite of coppcr as the former mineral was a tribasic sulpl.ars~niate. Both of these minerals when digested in solutions of the alkaline sulphides lose weight and the greater part of the sulphide of arsenic is dissolved. In like manner the dark and light varieties of Rosicler may be considered as tribasic sulphantimonite and tribasic sulpharsenite of silver. Specimens of great purity of the dark variety gave- Silver .. 5901 Antimony . . 23.16 Sulphur . . 17-45 9962 Or 3AgS . SbS, and the light variety :-Silver . 64-88 Arsenic . . 15.12 Sulphur . . 19.81 99.81 corresponding to 3AgS .ASS,. Specimens have been forwarded for the acceptance of the Society to the care of Blr Abel. I am at present engaged in the investigation of a mineral containing sulphur antimony copper and iron with small quan-tities of silver. The blackish-looking ore is thickly sprinkled with bisulphiile of iron and as yet I have obtained no specimen pure enough for analysis. From the relative proportions of antimony aud copper little doubt exists that it will prove to be a tribasic sulphantimonite of copper.

ISSN:1743-6893    

DOI:10.1039/QJ8601200008

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

13 111.-On Titanic Acid. BY E. RILEY,F.C.S TIT-4NIC acid from its great similarity to sihcic acid is frequently overlooked in the analyses of silicates although it occurs in many instances in some quantity. The properties of the two acids being so similar there arises great difficulty in separating them ; moreover the ordinary test for minute quantities of titanic acicl is unsatisfactory ; and it became necessary before commencing ex- periments on the subject to see if some better test than the ordinary one with microcosmic salt in the reducing flame of the blow-pipe either alone or with the addition of tin could not be suggested. It occurred to me from the remark made by Karsten viz. “That muffles made of Cracow clay used for the distillation of zinc assume a blue co1our”-that some reaction with this metal might be made available as a test for the acid.In trying zinc in various ways it was found when this metal was used in the reducing flame of the blow-pipe in the metallic state in conjunction with minute quantities of titanic acid that after the combustion of the zinc and clearing of the bead on cooling a very distinct coloration was always produced whereas the button of microcosmic salt and titanic acid being tried pre- viously in the ordinary way gave no reaction. By this test titanic acid may be found in pig iron and in most cases where any residue is left by treating silica with hydrofluoric acid. In the determination of silica (in the ordinary way by fusion with carbonate of soda) in several samples of fire-bricks it was always found that there was a considerable residue left after treat- ing the silica with hydrofluoric acid in Rrunner’s apparatus This residue consisting of a fluoride of titanium with possibly some titanic acid cannot be heated without the fluoride of titanium being volatilized; in fact by far the larger portion of it goes off.An experiment made on 2.235 grains of titanic acid exposed for some twenty-four hours (with the occasional addition of water) in Brunner’s apparatus until it was completely dissolved left on evaporating to dryness and beating carefully to a low red heat only a residue of -99 grains which still contained a trace of fluorine; hence it follows that the residues obtained by the same method as IiILEY ON TITANIC ACID.detailed in the above experiment from the silica of the fire-bricks represents only a portion of the titanic acid actually present. After the separation of the silica in these analyses the filtrate mas again evaporated to dryness and heated. A residue mas then obtained which was at first considered to be silica not having been rendered insoluble by the first heating. Through the whole series of analyses however in several cases of which the fusion after evaporating to dryness was subjected to very various temperatures some extending over a long time and heated to a high tempera- ture on a porcelain dish a residue was always obtained on evapo- rating the filtrate from the silica to dryness as will be seen from the table appended :- ~~~ ~~~ ~ Number.Weight of Fire-brick taken. Silica ob- tained. Residue on second evaporation Residue from Silica by HFI. Second evapo-ration. Resi- dueby HP1. 1 2 17.42 18.25 3 0.77 11.925 I *325 -41 -19' *22 -1 1 3 18.41 11.435 -42 -226 -07 4 17.74 10.41 1.115t *236 5 18-08 11.79 -39 ,135 -16 6 7 17-45 18.21 10.04 10.64 -375 -435 *13 -17 ,115 -11 8 18.325 10 325 -34 -165 -09 9 18.43 1116 .36 -19 -095 10 18.10 10.22 -34 *I9 *13 11 18-34 11-175 -41 -14 .13 Mean of 9 18.17 10.98 -386 .174 -112 The residue in column 4 had all the characteristics of titanic acid although it probably contains a small amount of silica; when heated it assumed the yellow tint of titanic acid and the residue left after heating with hydrofluoric acid shows that a large pro- portion of it was titanic acid. It may be mentioned that these residues were tested for alumina; only a trace was found. * Silica and residue on second evaporation added together and heated with HPI. + Some silica passed through filter in first filtration; both added together as in number one and treated with hydrofluoric acid.

ISSN:1743-6893    

DOI:10.1039/QJ8601200013

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

IV.-On the Constitution of Lactic Acid. BY DR. H. KOLBE. THErecent experiments of Messrs. Perkin and Duppa* on the action of ammonia on bromacetic acid having verified the opinion long ago put forth by many Chemists that glycocol stands to acetic acid in the same relation as amidobenzoic acid HO.C, {g:NlC,O,,O tobenzoic acid HO(C,2H,)C202,0 it follows that glycocol may be regarded as amidacetic acid HO. C (giN)C,O,,O just as Cahours has shown? that alanine has the composition of amidopropionic acid HO.C {giN)C20,,0 and leucine of amidocaproic acid HO.C, -fHIO C202,O. @,r\T) These several amidated acids resemble each other in many respects and particularly in this ;-that when their aqueous (not alcoholic) solutions are treated with nitrous acid,- they yield a new series of acids free from nitrogen related to one another in the same manner as the amidated acids are among themselves but dis- tinguished from the latter by the substitution of 1atom of hydrogen and 2 atoms of oxygen,-that is to say of the elements of peroxide of hydrogen,-for the amidogen decomposed by the nitrous acid.From these and other considerations it may be inferred that the so-called glycollic lactic and leucic acids are analogous in chemical constitution to Gerland’s oxybenzoic acid and bear the same relation to acetic propionic and caproic acids that oxybenzoic acid bears to benzoic acid. From these relations and from a careful consideration of thc entire chemical behaviour of oxybenzoic glycollic lactic and leucic acids I have come to the conclusion that these acids are simple substitution-products of the primary acids benzoic acetic propionic and caproic and are derived from them by the sub-stitution of a molecule of peroxide of hydrogen HO, for one atom of hydrogen thus-* Chem SOC.Qu. J. xi 22. + Ann. Ch. Phnrni. cviii 106. olycollic acid is oxaretic acicl HU.(C -I H )c,o,,o ; CHO Lactic acid is oxypropionic acid HQ.( (1 {;~l)C,O,,O ; Leucic acid is oxycaproic acid HO.( c, ~:@,o,,o ; and the compositioii of oxybenzoic acid is expressed by the rational formula HO.( C, (~@,O,?O. The relations between the above-mentioned primary acids and the amidated acids and oxyacids derived from them will perhaps be made clearer by the following tabular view HO.(C2HaW2OpO HO.(C2 { 22N)C20& HO. (c2 { c20210 Acetic acid. Amidacetic acid (glycocol). Oxyacetic (glycollic) acid. HO.(C,H,K&O2,0 HO (C { :”> C20,,0 HO. (C2 { H4 ) C202,0HO2 Propionic acid. Amidopropionic acid (nlanine). Oxypropionic (lactic) acid. HO.(C,,H,,)C,02,0 H 0( Clo{ g:pN) C20,,0 KO.(C,,{ :5Jc20290 H0.(C14H6)C202,0 Caproic acid HO. (C, { EiN )C202,0 dmidocaproic acid (leucine). HO. (%{ Zoo,)C202~0. Oxycaproic (leucic) acid. Benzoic acid Oxybenzoic acid. The idea that peroxide of hydrogen can play the part of an elementary body and replace the hydrogen in an organic radicle appears at first sight so paradoxical and improbable that I was at first inclined to reject it; and it is only after long and mature reflection that I have been able to convince myself of its validity.The history of modern chemistry furnishes numerous instances of the ultimate adoption of hypotheses which at first appeared as improbable and paradoxical as the above,-for example the replacement of hydrogen in organic radicles by chlorine and even by peroxide of nitrogen;-and I therefore think it probable that the preceding hypothesis respecting the constitution of oxybenzoic acid may some day meet with less opposition than it is likely to encounter at present. To decide the question whether glycollic and lactic acid ought really to hc regarded as derivatives of acetic and propionic acids CONSTTTUTIOX OF LACTIC ACID. 17 it is necessary to ascertain whether the Gr&-mcntioned acids can be directly produced from and reconverted into the second I am at present engaged with experiments bearing upon this point and have already obtained by the electrolysis of acetic acid mixccl with sulphuric acid an acid which I believe to be oq-acetic acid.The inverse transformation tdres place so easily and coni-pletely,-as shown by U lrich (see the next paper),-tliat lactic acid will probably be found the best material for preparing large quantities of chemically pure propionic acid; and there is 110 doubt that oxyacetic and osycaproic acid may iu like manner bc easily converted into acetic and caproic acid. The preceding views are apparently incoiisistent with Wizr t z’s recent statement? respecting the behaviour of lactic acid with yentachloride of phosphorus and the products of decomposition of the resulting compound called by Wu r t z chloride of Zuciyl.From these facts indeed W ur t z has drawn conclusions totally different from the above and has in particular endeavoured to show that lactic (with 6 atoms of carbon) is a hibasic acid 2HO. (C6H402)0,. But ,the very facts vhich Wurtz brings forward in support of this view appear to me to prove ths correctness of nip own hypothesis on the constitution of lactic acid; indeed a single perusal of Wurtz’s memoir sufficed to convince me that his chloride of lactyl C6H,02,C3 is in reality the chloridc~ of chlorpropimy! (C4(Ef) C202,C1 (Iiomologous with chloridc of chloraceton~-~,(C2-fFf)C,02,Cl) ziid that tlie transfor-mation of lactic acid intb this compound by treating its lime-saIt with pentachloride of phosphorus takes place as represented by the equation Lactate of lime.Chloride of chloropropioxyl. + 2PO,C1 + CaCl 4-HC1; further that JT ur t z’s chlorolactic ether is chloropropionate of ethyl C,HS0.(C4 {$)C20,,0 produced according to the equation ~ * Ann C‘h. Z’hwni. cvii 194. VOL. XTI. C ( C {~i)c~o~,cl + C,II~O.HO = c,H,o.(c,(~)c,o,,o Chloride of chlorpropioxyl. Chloropropionate of ethyl. + HC1; and that it will be easy from these compounds to produce propionic acid itself. The experimental investigation of these questions has heen undertaken by Dr Ulrich who has shown that the product of the action of pentachloride of phosphorus on lactate of lime is 1 eally thc chloridc of cliloropropioxyl ; that this compound is converted by water into chloropropionic acid ; that Wurt z’ s chlorolactic ether is chloropropionate of ethyl ; and that either of these compounds when subjected to the action of water and nascent hydrogen easily reproduces propionic acid (see tlic following memoir).I therefore regard it as certain that lactic acid contains 6 atoms of carbon,-not 12 atoms as some chemists suppose,-and that it is monobasic and a derivative of propionic acid from which indeed it differs only by the replacement of one atom of hydrogen in the radicle by peroxide of hydrogen. Wvrtz has made the interesting observation that the so-called glycols liydrated oxidc of ethylene ‘231 C20,.2H0 hydrated oxide of propylcce ‘4’’5’ C202.2H0 ad liydi*ated oxide of HJ amylene ‘8‘’9? 11 J C20,.2H0 are converted by oxidation into oxy-acids viz, oxyacetic oxgpropionic and oxyvaleiic (butylactic) acid 110.(C {z60,)C,O2,0 respectively and hence concludes* that the glycols are the alcohols corresponding to theacids of the lactic acid series.In another paper,? which appeared a few months earlier Wurtz puts forth the opinion that oxalic acid is the acid corresponding to hydrated oxide of ethylene his words being as follows Bibasic oxalic acid may therefore be regarded as standing to the bi-acid compound gljcol in the same relation as acetic acid to ordinary alcohol,”-a view likewise entertained by other chemists. I regard both these views as decidedly false.The notion that glycols should be classed among alcohols is quite unfounded. However useful it may be to regard a number of heterogeneous * Ann. Cli. Phsrui. cvii 199. .F Ann. Ch. Pharm. ciii 368. CONSTITUTION OF LAOTIC ACID phenomena from one general point of view the attempt to extend the idea of an alcohol BO far 8s to include the so-called glycols is totally destitute of scientific value ; indeed by this unnecessary generalisation we rather incur the danger of losing altogether the definite conception of an alcohol. We have hitherto included in the class of alcohols the hydrated oxides of monatomic radiclee which besides many other general characters resemble each other especially in thie reepect that under the influence of oxidising agents they take up an atom of oxygen in place of an atom of hydrogen at the same time giving up their atom of basic water and are converted into aldehydes,- and subsequently by taking up two more atoms of oxygen into the corresponding acids.Now the first of these properties via. the power of generating aldehydes by oxidation is altogether wanting to the glycols For independently of the fact that no aldehyde has yet been prepared from either of the said so-called glycols it may be shown h priori by comparison of the rational formulae of ethyl-alcohol C,H,l C,O.HO and hydrated oxide of ethylene H (ethyl-glycol) ‘SE31 C20,.2H0 that the latter cannot like the former be converted into an aldehyde by oxidation. If in hydrated oxide of ethylene 1atom of hydrogen be converted into water and replaced by 1atom of oxygen-that is to say-if the compound be subjected to a process of oxidation analogous to that by which alcohol is converted into aldehyde the product must evidently be not an aldehyde but a body having the composition of acetic acid : c2E3) C20,,2H0 + 20 = (C,H3)C20 + 3330 this product will in fact either be hydrated acetic acid or a 1)ody homologous with hydrated oxide of lipyl (C,H,) C,,03.3H0 viz.hydrated teroxide of acetyl (C,H3)C2,0,.3H0. And by further substitution of an atom of peroxide of hydrogen for an atom of hydrogen in the acetyl oxyacetic acid is formed a corn-pomd which indeed Wurtz actually obtained as a product of the oxidation of hydrated oxide of ethylene.To these observations it may be objected that Debus’s glyoxd C,H,O, is the aldehyde which atands between hydrated oxide of ethylene and oxyacetic (glycollic) or oxalic acid (whichever of these c2 KOLBE ON THE acids may now he regarded as corresponding to hydrated oxide of ethylene or to glyosal). But before entering upon this question it mould be well to decide whether we are justified in regarding glyoxal as an aldehyde. The property of passing by oxidation into one or two acids richer in oxygen than itself and that of uniting with alkaline bisulphites are possessed by glyoxal in com-mon with many other bodies which are not aldehydes. But even granting that glyoxal may be an aldehyde it is certainly not the aldehyde of hydrated oxide of ethylene or of oxyacetic glyoxylir or oxalic acid.Whatever view we may take of its constitution the process by which it is converted into oxyacetic acid is certainly quite unlike the formation of acetic acid from aldehyde for the latter is simply a process of oxidation consisting in the mere assumption of 2 atoms of oxygen ;whereas the former depends upon the addition of 2 atoins of water to the constituents of glyoxal C,€I,O,& + 2H0 = H0,C4H,0 GIyoxal. Oxyacetic acid. I regard glyoxal provisionally as constituted according to the formula (C2 {EO,)C,O, that is to say as the bioxide of the biiltomic radicle (C2 f €1 )C2 in which the member WO (.C2 osymethylenc,-a derivative of methylene C2H2,-is combined with carbonyl.The transformation of glyoxal into oxyacetic acid may then be rationally expressed by the following equatioii :-Glyoral. Oxyncetic acid. With respect to the chemical constitution of the so-called glyoxy- lic acid I suggest that it may be a further substitution-product of acetic acid of the same kind as oxyacetic acid viz. bioxyacetic acid HO. (C HO C,O,,O = H0.C4H30, that is to say go) acetic acid having 2 At hydrogcn in the radicle replaced by 2 At. peroxide of hydrogen :- CONSTITUTION OF LACTIC ACID. HO. (C2II,)C,O2,O Acetic acid. (:a,) 110.(C C,O,,O Oxyacetic (glycolic) acid. C,O,,O Bioxyacetic (glyoxylic) acid. HO Similarly I am of opinion (and am at present engaged nith experiments relating to the matter) that ylyceric acid discovcrcd not long ago by Debus is bioxypropionic acid and that it stands to lactic and propionic acid in tlie same relation as bioxyacetic acid to oxyacetic and acetic acid HO.(C,H,)C,O,,O Propionic acid. HO.(C {E~,)c,o,,o oxypropionic (lactic) acid. HO.( C HO C,O,O Bioxypropionic (glyceric) acid. g;) If t-lowever-and of this I am convinced-oxyacetic and oxypro-pionic acid do uot stand to hydrated oxide of ethylene and hydrated oxide of propylene in the same relation as acetic and propionic acid to ethyl-alcohol and propyl-alcohol it still remains a question whether the aldehydes and alcohols correspondiiig to osyacetic and oxypropionic acid have any existence. Of this I have no doubt and even consider it easy to prcdict how these aldehydes and alcohols must be constituted.With regard to their empyrical constitution they mill bear to oxyacetic and oxypropionic acid the sanie relation that the cmpyrical forinulte of aldehyde and ;tlcohol bear to that of acetic acid that is to say they will differ from the corresponding compounds of the acetic acid series by containing 2 additional atonis of oxygen as may be seen from the filloaing table :-HO.C,H,O C4H40 C4H50.H0 Acetic acid. Acetic aldehyde. Acetic (ethjlic) alcohol. HO.C,H,O C*H*O* C4H503. HO Oxyacetic acid. Oxyacetic aldehyde. Oxyacetic alcohol ICOLBE ON THE H0.C6H503 C6H602 C,H,O.HO Propionic acid. Propionic aldehyde. Propionic alcohol. HO.C,I-I,O W60 C6H,0,.H0 Oxypropionic acid.Oxypropionic aldehyde + Oxypropionic alcohol. Among known compounds anisic acid nnisic aldehyde and anisic alcohol may be mentioned as similarly related :-H0.c 6H,O C,,H,O C~~H~O~.KO Anisic acid. Anisic aldehyde. Anisic alcohol. It may also be observed that anisic acid is related to toluylic acid so far as its rational constitution is coricerned-in the same manner as oxypropionic acid to propionic acid-and that generally the aldehydes and alcohols of osyacetic oxypropionic acid and anisic acid may he regarded as derivativesof the primary aldehydes and alcohols in the same sense as the oxyacids themselves are derivatives of acetic propionic and toluylic acid. The following formulae are given as the symbolic expression of my views of the rational constitution of thew compounds :-Acetic acid.Acetic aldehyde. Acetic (ethylic) alcohol. (c {5,}C2O2 Oxyacetic acid. Oxyacetic aldehyde. Oxyacetic alcohol. Propionic acid. Propionic aldehydc. Propionic alcohol. Oxypropionic mid. Oxypropionic aldehydc. Oxypropionic alcohol. Toluylic acid. Toluylic alcohol. Toliiylic alcohol. * Oxypropionic aldehyde wouId be isomeric with hydrated propionic acid acetate of methyl and formatc of ethyl ;oxyacetic aldehyde with hydrated acetic acid $c. CONSTITUTION OF LACTIC ACID. Anisic acid. Anisic aldehyde. Anisic alcohol. The fundamental idea of these formulze of alcohols and altle-hydes will be more fully developed in a future communication.

ISSN:1743-6893    

DOI:10.1039/QJ8601200015

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

CONSTITUTION OF LACTIC ACID. V.-Conversion of Lactic Acid into Propionic Acid. BY Dr. C. ULRICH. THEfollowing experiments were undertaken at the suggestion of Professor XColbe with the view of testing the correctness of tlic supposition that the compound recently obtained by Wint z from lactic acid and described by him as chloride of lactyl C6H40,.C1 is the chloride of chloropropioxyl (c,{ Ef) c,o,,c~. If t~iis view be correct the supposed chloride of chloropropioxyl may lie expectea to decompose with water into chloropropionic and hydro-chloric acids and the product of the action of alcohol on tlmt compound described by W ur t z as chlorolactic ether will exhibit the characters of cbloropropionate of ethyl Chloride of chloropropioxyl. Chloropropionic acid.(C4 (cHi)c,O,,cI+ c4H50,H0 =C,H,O(C {Ff)C202,0 +HCI Chloride of chloropropioxyl. Chloropropionate of ethyl. The assumption that the compound formed from the so-called chloride of lactyl by the action of water is chloropropionic acic? is opposed to the statement of Wur t z that the acid produced in this reaction is lactic acid. I have however repeated the experi- ment and found as I expected that the re-production of lactic ULRICH ON THE CONVERSiON OF LACTIC AClD acid by the action of water OLI chloride of lactyl takes placc oiily when an alkali or other strong basc is lilreivise present; and that when the decomposition is produced by the action of water alone the resulting conipound is not lactic but cliloropropionic acid. The colourless fuming liquid (the mixture of chloride of chloro- propioxyl and oxychloride of phosphorus) obtained by heating dry lactate of lime with pentachloride of phosphorus was added by small portions to a.largc quantity of water and the acid liquid containing considerable quantities of phosphoric and hydrochloric acid was distilled to about half its bulk. The distillate contained lipctrochloric acid and as I shall presently show chloropropionic acid. The residue in the retort which should have contained lactic acid if that acid had been formed was further evaporated in thc water-bath in order to expel the remaining chloropropionic acid as coniplctely aspossible and then tested for lactic acid; it did not liowerer afford any ilidicntion of tlie presence of that ucid.The acid distillate containing the chloropropio~~ic acid was iieutralised in the cold with recently precipitatcd carbonate of silver ; the filtered saline solution mas evaporated to dryness over sulpI~uric acid in racuo ; aiid the chloropropionate of silver which crj-stallised from it in beautiful colourless square prisms was ana- lysed. I had found by a preliminary esperimeut that the salt when heated gave off acid vapours aid left a rcsidue consisting cliiefly of cliloride of silver but containing also a certain quantity of metallic silver ; in fact a small portion of the chloropropionic acid evaporates undecomposed when the silver- salt is heatcd as shown by the odonr of thc acid vapours; if this were not the case the residue would consist entirely of chloride of silver.0.478 grm. dried in V~CUO gave aftcr being heated 0.299 grm. of a mistnre of chloride of silver and nietallic silver. This resi-due after being heated to a temperature short of its melting point was warmed with nitric acid and the liquid evaporated to dryness after addition of hydrochloric acid. On ignition there remained 0.319 grin. of fnserl chloride of silver corresponding to 50.2 per cent. of silvcr. 0.710 grm. burnt with oxide of copper yielded 0.430grm. of carbonic acid and 0.121 grm. of water (= 16.5 p. c. carbon and 1.9 p. c. hydrogen). These numbers agree very nearly with the calculated composition of chloropropioaate of silver. Cslculltted. Ponnd. 6C . . 36.0 16.7 16.5 4H b * 4.0 1.9 1.9 c1 .355 16.5 --4g . 108.0 50.1 50.2 40. . 32.0 14.8 -C6H,Clhg0 . 215.5 100.0 Chloropropionate of silver is much more soluble in water thau the propionate. It is but little blackened by light. On boiling the aqueous solution chloride of silver is dcposited and lactic acid is doubtless formed. The same decomposition takes place during the evaporatioir of the aqueous solution on the water-bath. Chloropropionic acid is much less volatile than propionic acid and has an odour like that of terchloracetic acid. As it seemed desirable to adduce still further proof that the acid obtained as above is really chloropropionic acid I endeavoured to convert it directly into propionic acid. This was effected as follows The crude chloride of chloropropioxyl still containing oxy-chloride of phosphorus was made to flow gradually into water contained in a vessel well cooled from without and having at bottom a tolerably large quantity of finely granulated zinc.The hydrogen evolved by the mutual action of thc water the zinc and the phosphoric and hydrochloric acids was expected to replace the chlorine in the chloropropionic acid produced by the action of the water on the chloride of chloropropioxyl. An abundant evolution of gas immediately took place; and when at length the drops of oil had disappeared and the odour of chloride of chloropropioxyl and oxychloride of phosphoriis mas uo longer perceptible the acid liquid was decanted from the zinc diluted with water and dis- tilled.The watery distillate contained besides traces of hydro-chloric acid a considerable quantity of pure propionic acid. This liquid was neutralised with carbonate of soda ; the saline solution evaporated to dryness; and the dry nims distilled with dilute sul- phuric acid. A portion of the strongly acid distillate which smelt distinctly of propionic acid was boiled with carbonate of silver and the solution filtered while hot. It theu on cooling deposited pure propionate of silver in fine crystals which slowly blackened when exposed to light. ULRICH ON CONVERSION OF LACTIC ACTD &C. 0.331 grm. of these crystals dried over sulphuric acid left on ignition 0.198 grm. of metallic silver. 0.4495 grm. burnt with oxide of copper gave 0.330 grm.car-bonic acid and 0,116 grrn. water. Calculated. Found. 6C. . 86 19.9 19.6 5H . 5 2.7 2.8 Ag . 108 59.6 59.8 40 . 32 17.8 C6H,Ag0 . 181 100.0 I have also prepared the potassium-salt and decomposed 0.3985 grm. of it with strong sulphuric acid. After strong and continued ignition this quantity of the salt left 0.314 grm. sulphate of potassium corresponding to 35.3 p. c. potassium. The formula K0.C6H,0 requires 34.8 p. C. The ahove-described method of preparing propionic acid is so productive and yields so pure an acid that it is perhaps to be preferred to all other methods. Lastly I have treated chloroyropionatc of ethyl (TVurtz’s chlo- rolactic ether) boiling constantly at 143°C. with zinc and dilute sulphuric acid with the hope of converting it into propionate Gf ethyl.The liquid soon exhibited a considerable amourit of hydro.. chloric acid but in the subsequent distillation yielded only traces of propionic ether with considerable quantities of propionic acid. 0.4635 grm. of propionate of silver prepared therefrom yielded 02755 grm. metallic silver = 59.441 p. c. (calculated quantity 59.66 p. c.). Propionate of ethyl appears therefore at the moment of its formation from chloropropionate of ethyl to be resolved into pro-pionic acid and alcohol perhaps in consequence of the decomposing action of the free sulphuric acid present.

ISSN:1743-6893    

DOI:10.1039/QJ8601200023

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

27 VI.-On some Native Combinations of Oxide of Mercury with Oxide of Antimony. BY FREDERICK FIELD. M. Do M EY IC 0,in an extended memoir upon the minerals of Chili pinblished in the Annales des Mines 4 series vol. vi p. 183 mentions a red piilverulent substance found in small quantities in the cavities and upon the sides of grey uaercury ore. This snb-stance it is said forms an impalpable powder is scarcely attacked by hydrochloric acid but dissolves easily in nitric acid without disen- gagement of sulphiiretted hydrogen. Dana in the third edition of his Mineralogy page 534 mentions the mineral ammiolite from appov (vermilion) discovered by Domeyko the same doubt- less as that described in the Annales desMines and having the following composition :- Antimonious acid (SbO,) .12.50 Oxide of mercury . 14-00 Sesquioxide of iron . . 22.30 Silica . . 26.50 Water and loss . . 24.70 1oo*oo I have lately obtained very fine specimens of a red mercurial mineral differing very much in constitution from the above apparently of some interest to mineralogical science as the mercury exists to a great extent in an oxidized coiidition associated with teroxide of antimony. The specimens alluded to were obtained from the surface of a hill near Tambillos about 9 leagues east of Coquimbo in a porphyritic formation. The mineral however itself being immediately associated with hydrated oxide of iron and car-bonate oi lime I caused the min to be csplored to the depth of about 20 yards and obtained a considerable quantity of ore running in small veins along the lode and occurring at intervals in rounded masses and nodules.The mineral which had a bright red colouir was occasionally very much mixed with many others of 3' PJELD ON CUMBINATLONS OF a wry opposite clcscription. In one specimen alone weighing oiily a fcm ounces tlic following merc observed :-lo A small vein of a ncm variety of mercurial fahlore of a dark crimson colour highly lustrous and metallic coritaining inercury copper antimony arsenic zinc and sulphixr 2" A scarlet wassivc substance consisting of oxide of mercury oside of copper oxide of antimony sulpliide of antimony sulpliidc of mercury arid small quantities of osiclc of iron and mater. Crystals of ospcliloride of copper (atacamite).4P Green carbonate of copper. 5O Blue carbonate of copper. 6' Black silicate of manganese and copper 7O Hydrated oxide of iron. The five latter substances were scattered about tlie mineral and could be more or less separated from the red mercurial ore by the hammer It may be imagined that it wasa matter of extreme difficulty to obtain a sufficient quantity of pure substance for the purpose of qaantitstive analysis but having more than 1201bs. of specimens at my command 1 was enabled to select some very fine samples. Great doubt still exists regarding the copper as to whether it forms an esseiitial part of the mercury ore or is only in close mechanical coniiection with it. The following researches may tend to clear up in some degree certain points which have hitherto been rather obscnre although froin thc earthy nature of the riiiicral and the entire absence of crystallisation there is still room for doubts as to its true forinula- 100 graiiis of the earthy red mass freed as much as possible from all foreign ingredients gave as a mean of three analyses the following numbers :-Copper .16.66 Mercury . 27.52 Aiitimony . 10.21 Chlorine . 050 Sesquioxidc of iroii 2.18 Carbonic acid . 2.10 Water . 5.65 Sulphur . 4.01 Silica . . 23.38 On examining the pulverised mineral with a lens bright green particles were observed among the scarlet powder consisting partly of carbonate and partly o€ oxychloride of copper. No mechanicd means could separate these substances and the above analysis clearly shows that at least two well-known mincrals are associated with the one under examination.The sulpliur exists partly in combination with the antimony and partly with the mercury as the prolonged action of hydrocldoric acid dissolves the whole of the former metal as well as all tlie copper leaving small particles of sulphide of mercury undissolvecl and disengaging sulphuretted hydrogen from the decomposition of the sulphide of antimony. The loss in thc analysis is chiefly due to oxygm and by combining that element with the metals we have the fo1lo.c~ ing composition of the mixture :- Carbonate of copper (CuO.CuO,CO,) 9.73 Oxychloride of copper (3Cu0,CuCl) . 2.62 Oxide of copper .ll*CO Teroxide of antimony . . 6.244 Tersulphide of antimony . . 7.01 Oxide of mercury . . 1G.22 Sulphide of mercury . . . 14.50 Sesquioside of iron . . 2.12 Water . . . 5.65 Silica . 2,3*38 98.47 It occurred to me that perhsps the action of weak acids might remove many extraneous matters apparently not imme-diately connected with the mineral aid also throw some additional light upon its constitution. Action of Hydrochloric Acid. When the scarlet powder is digested with warm dilute hydro- chloric acid slight evolution of sulphuretted hydrogen takes place and the whole of the copper and part of the mercury and antimony are dissolved; the residue which has a light pinkish colour consists of silica mingled with particles of undecomposed ore.Strong boil -ing hydrochloric acid attacks it poweriully disengaging sulphu- retted hydrogen and dissolving the whole of the copper and antimony and the greater part of the mercury. The residue Elas still a light red coloiir aid contains about 2 per cent. of mlphur the rernain- no FIELD ON COHRINATTONR OF der of that element having been eliminated as hydrosulpliuric acid. The addition of iodide of potassium to the hydrocliloric acid solution precipitates iodide of mercury which is redissolved by an excess of thc precipitant; but no free iodine is evolved proving that the antimony exists as SbO and not SbO or SbO,. A mixture of hydrochloric acid and clilorate of potash attacks the mineral with considerable energy and if it is in a very attenu- ated state decomposes it completely after some time.Aqua regin exerts a similar action. Ordinary nitric acid dissolves all the copper but scarcely aity antimony or mercury. The powder assumes a brighter scarlet colour from the abstraction of the green particles of carbonate and oxychloride of copper which diminish its brilliancy. The strongest fuming nitric acid affects it but little; like the otlicr reagents above mentioned it abstracts all the copper. IIcatcd in a glass tubc the mineral loses water even beyond 212",but rcgairis its original weiglit after a few hours exposure to the air. From the above reaction it would appear that the mercury and antimony are in a peculiar state of combination forming a definite compound in which the copper takes no part.Although oxide of iiicrcury is rery soluble in nitric acid little or none is dissolved uhen it is in association with teroxide of antimony although thc wliole of the copper is imniecliately extracted wen when the acid is extremely dilute. Acetic acid also when gently warmed dis- solves the whole of the copper after two or three days while the red mineral augments in brilliancy of colour and falls to the bottom. These facts lead me to believe that the copper is only mechanically mingled with the mercurial compound more espe- cially as very few specimens contain the same amount of cupreous inatters'; but after digesting the mass in dilute nitric acid the other elemeuts are found in certain relative proportious.This is still more probable from the fact that in the mineral as it is talcen froin the earth various shades of red from scarlet to crimson are observed depending evidently upon the greater or less amount 01 copper contained. After digestion in nitric acid the residue froni nearly all samples has the same colour. After very fine division a quantity of the mineral was digested in dilute nitric acid for some days. The solution had a dark blue colour and contained much copper and some iron but scarcely traces of sulphur mercury or antimony. There was also a small quantity of arsenic. OXIDE OF MERCURY WITH OXIDE OF ANTIMONY The powder when thoroughly dry was nnalysed and yielded :-Mercury . . 34.42 Antimony . . 14.21 Sulphur . . 5.43 Sesquioxide of iron .. 2.68 Water . 4.46 Silica . 35.50 96-70 Another sample freer from silica gave :-Mercury . . 37.94 Antimony . . 15.26 Sulphur . . 5-98 Sesquioxide of iron . . 2-94 Water . . 4.98 Silica . 29.78 96-88 By dividing the sulphur equally between the mercury and antimony making the former a simple and the latter a tersulphide and oxidising the remainder of each metal we obtain :-No. 1. No. 2. Oxide of mercury . . 15-16 20.79 Sulphide of mercury . 20.31 21.68 Teroxide of antimony 8.92 9.3% Tersulphide of antim ony . 9.48 10.46 Sesquioxide of iron . . 2.68 2.94 Water . . 4-46 4.98 Silica . . 35.30 29.78 99.51 99.97 Considering the silica and oxide of iron as accidental irn pnrities we have after deducting the water :-No.1. No. 2. Oxide of mercury . 31.77 33.36 Sulphide of mercury . 35.53 34-83 Teroxide of antimony . 15-61 14-92 Tersulphide of antimony 16.52 16.77 -._I 99.43 99-88 FIELD ON COMBINATIONS OF The mean of wlricli would be as undcr :-Oxide of mcrcury . . . 32-56 Sulphide of mercury . . 35.18 Teroxide of aiitirnoiiy . . . 15.27 Tersulphide of antimony . . 16.64 99.65 Little doubt can exist I imagine that this red mineral is the product of a partial oxiilatioii of a natural compound of sulphur antimony mercury and copper and that the oxide of the last metal is either only mechanically mixed or in very feeble com- bination with the sulphidcs and oxides of the other metals. The sulphide of mercuiry acts doubtless as a sulphur-base the sulphide of antimony being the sulphur-acid mhi4st the oxide of mercury plays the same part witli regard to the teroxide of antimony which in this instance also acts as an acid.The mineral may then be considered as a tribasic siilphantimonite of mercury combined witli tribasic aiitimonite of the same metal (3HgS,SbS,) + (3IlgO,SbO,) which requires the following numbers :-Oxide of merciiry . . 32.93 Sulphide of mercury . . . . 35.3'1 Teroxide of antimony . . 77-07 Tersulphide of aiitiniony . 1606.3 10000 The formula of the mineral may also possibly be the following 3(2HgO,€IgS) + (2SbS,,SbO,) which lias exactly the sainc pcrcentage composition as thc former and may be regarded as an oxysulphide of mercury couplcd witli an oxysulphide of antimony.The compound BSbS,,SbO is already known but 2HgO,HgS has not yet I believe been described. On the Sepumtion of Mercu~y fiona Antimony. Sulphide of mercury is perfectly soluble iu the sulpliides of potas-sium and sodium but scarcely so in the sulphides of ammonium. Weber tells us that in the presence of free alkali certain double compounds are formed tritli the alkaline sulphides and sulphides of mcrcurp. Free alkali however is not neccsswg. Crystalliserl OXIDE OF MERCURY WI TIE OXIDE OF ANTIMONY. monosulphide of sodium when in solution at once dissolves sulphide of mercury; when a solution of corrosire sublimate is dropped into one of the alkaline sulphates the black precipitate is immediately dissolved and the liquid remains perfectly colourless and clear.When this solution is exposed to the air for some days hydrosulphite of soda is formed and sulphide of mercury separates as a crystalline deposit. When the compound is placed in stoppered bottles it remains many months without decomposition. The sulphide of mercury evidently acts as an acid and may with propriety be termed sulphydrargic and its salts sulphydrargates. When a solution of arsenite or arseniate of an alkali is poured into sulphydrargate of sodium sulphide of mercury being the weaker acid is displaced and sulpharsenite or sulpliarseniate of the alkali is formed Although acting as a base towards sulphide of antimony it acts as an acid towards the alkaline siilphides; and thus if the red mineral for example be digested in a solution of sulphide of sodium it is nearly all dissolved silica sulphide of iron with traces of sulphide of mercury forming the residue.It may be imagined that in the first of the analyses mentioned great practical difficulties were experienced in the separation of the antimony from the copper and mercury inasmuch as by the application of sulphide of ammonium considerable quantities of copper were dissolved and by employing either of the other alkaline sulphides nearly all the mercury was dissolved with the antimony. A very perfect separation of the sul-phide of antimony from mercury appears to be obtained by digesting these compounds in moderately strong hydrochloric acid when all the sulphide of antimony is dissolved but not a trace of sulphide of mercury.A distilling apparatus is necessary as chloride of antimony is slightly volatile in the vapour of hydrochloric acid. If the two sulphides are digested in a retort connected with a condenser the distilled liquid should be added to that separated by filtration from the sulphide of mercury when the digestion is completed and the liquid after great dilution precipitated by sulphuretted hydrogen. Even when copper is not present it is difficult to get rid of the antimony from the mercury by means of sulphide of ammonium and with this reagent traces of sulphide of mercury are dissolved. In order to prove the accuracy of the separation by means of hydrochloric acid the following experiments were tried :-1.00 gr.tersulyhide of antimony was dissolved in hydrochloric VOL. XII. D FIELD ON ~OMI~~NI\’IIO~’S 34 OF ;I(;icl and 12.00 of protochloride of mercury added. The metals were precipitated by hydrosulphuric acid and the sulphides digested in strong warm hydrochloric acid the vapour of which was condensed and added to the filtrate. After dilution with water the liquid was saturated with sulphuretted hydrogen and at the expiration of twenty-four hours the sulphide of antimony collected on a tared filter dried and weighed. The sulphide of mercury was washed collected and estimated. Taken. Found. SbS . 1.00 = 0.71 Sb. SbS . . 0*96 = 0.685 HgCl . . l2*00= 8-82Hg. HgS . . 10.41 = 8.973 9.53 9.658 Another experiment in which I.00gr.HgC1. and 12 grs. Sb.S were taken gave :- Taken. Found. 1.00 Hg.C1. = 0735 0.856 HS = 0.7‘37’ 12-00Sb.S = 8.571 11.890 SbS = 8.493 -7 9-306 9.230 As the red mineral is perfectly decomposed by acids only when in the finest state of division a very convenient method is to digest the powder in a strong solution of sulphide of sodium. The residue consists of silica with sulphide of iron and traces of sulphide of mercury while the filtrate contains the whole of the antimony and the greater part of the mercury. If the residue is now treated with hydrochloric acid and chlorate of potash the silica remains perfectly white and the mercury may be precipitated by sulphuretted hydrogen. The small quantity of sulphide of mercury is added to the sulphide of sodium solution acid is introduced and the whole boiled until disengagement of sul-phnretted hydrogen ceases.The sulphide of mercury together with uncombined sulphur is washed upon a tared filter dried at 212O and weighed. A portion is taken and the sulphur is estimated in the usual manner from which the weight of mercury is calculated from the whole amount of precipitate. The antimony is pre-* The late experiments of Schneider confirmed by Rose have shown that the equivalent of antimony as stated by Berzelius is far too high. Berzelius gives it as 129 or 64.5. Schneider as 120 and Rose as 120.60. I have adopted 125. OXIDE OF MERCURY WITH OXIDE OF ANTIMONY. cipitated from the diluted solution by sulphuretted hydrogen and the sulphur also estimated the antimony being calculated as loss.Although apparently differing in many essential points from the red mercurial ore of M. Domeyko more especially with regard to the action exerted upon it by hydrochloric and nitric acids it is doubtless only a variety of the same mineral derived from the oxidation of mercurial fahlore. I have thought it as well there- fore not to designate it by any new appellation but at present at least to call it arnmiolite a name given to it by its distinguished discoverer.

ISSN:1743-6893    

DOI:10.1039/QJ8601200027

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

OXIDE OF MERCURY WITH OXIDE OF ANTIMONY. VIL-On a New Method for the Quantitative Estimation of Nitric Acid. BY DR. E. PUGH. IN a paper read before the Chemical Section of the British Association for the Advancement of Science at Leeds for 1858 the author gave the chemical principles involved in a new method for the determination of nitric acid together with some results illustrating the accuracy of the same The object of the present paper is to give some details of manipulation a knowledge of which is essential to the successful use of the method as also to indicate some collateral points involved in cases of nitric acid determinations that are likely to occur. The difficulties of estimating small quantities of nitric acid by any of the known methods were sufficient to make it desirable that some better methods should be known.The great reducing power of the subchloride of tin suggested the idea of using it to deoxidise nitric acid; and the very exact method of August Streng (Yogg. Ann. xcii 57) of estimating the amount of tin oxidised and hence the amount of nitric acid reduced seemed to offer the necessary conditions of success. 8 1. Streng’s method consists in ascertaining how much of a solution of bichromate of potash of known strength is necessary to convert a given amount of protochloride of tin in chlorhydric D2 PUGH ON A NEW METHOD FOR THE acid solution into perchloride ; the point of complete chloridation being known by the deep blue colour produced by the liberation of iodine from iodide of potassium in presence of starch by the first drop of bichromate solution above that necessary to raise the protochloride to perchloride.62. This method is recommended by the ease with which the reagents are obtained in R state for use and by the absence of any tendency on the part of the bichromate solution to change on keeping and most particularly by the characteristic action that marks the point of complete oxidation. 63. An attempt to reduce nitric acid in open vessels gave no constant results; nor mas the experiment more successful when conducted in vessels from which the air had been exhausted by repeated pumpings and subsequent influx of carbonic acid. This corresponded with the results of Dr. Mohr who in 1855 says in his Lehrbuch der Titrirmethode p.218 that he found an amount of oxidation corresponding to more than three atoms of oxygen for each atom of nitric acid present from which he erroneously concluded that protoxide of nitrogen or even nitrogen gas mas evolved in the process. 0 4. In a great number of experiments in which the time of boiling under carbonic acid gas varied from 30 minutes to 6 hours and in which almost all possible proportions of nitric acid chlo- rhydric acid and protochloride of tin were used no conditions could be found that mould give constant results. The amount of oxidation obtained varied from 3 to 6 atoms of oxygen for every atom of oitric acid present; and ten hours boiling was not suffi-cient to raise the oxidation above 7 atoms.And what was re- markable it was possible to get an amount of oxidation from 3 or 4 millegrammes of nitric acid corresponding to 4 or 5 atoms of oxygen while with -060grins. of nitric acid the proportional amount of oxidation was very little higher. This would seem to indicate either that on long boiling the nitric acid acquires a passive state with regard to the proto- chloride of tin or that there is a more or less stable interme- diary compound formed during the reaction beyond which the oxidation cannot be carried without a higher temperature. 8 5. An examination of the carbonic acid over the fluid after the reaction showed the absence of nitrogen and protoxide of nitrogen. The fluid on the contrary was found to contain am- monia which corresponded in quantity with the amount of tin QUANTITATIVE ESTIMATION OF NITRIC ACID.subchloride oxidised and hence suggested an explanation of the reaction by the formula NO + 8 (SnC1 + HC1) = NH + 8SnC1 + 5HO 0 6. On raising the temperature in a closed vessel to 140"for half an hour the oxidation effected was equal to that of 8 atoms of oxygen for each atom of nitric acid present ; arid at a tempera-ture of 170° the reaction with *060grms. of nitric acid was COM-pleted in 10 minutes; it being indeed only necessary to raise the temperature to this point ill an oil-bath and then remove the lamp and allow the reaction to take place during the few minutes the temperature of the bath was rapidly falling. These reactions suggested the following process 7.To make an aqueous solution of bichromate of potash of such strength that a. times the unit of weight of salt wiil be contained in b. times the unit of volume of the solution. Then the unit of volume of the solution will contain -a units of weight b of the salt. And take of a solution of protochloride of tin with great excess of clilorhydric acid a quantity sufficient to reduce at least one- fourth more nitric acid than is supposed to be present in the substance to be examined. Then ascertain the number n of units of volume of the bichro- mate solution required to chloridate this quantity. Digest a like quantity in a sealed tube with the nitric acid to be determined in an oil-bath at 170° for 10 minutes and then ascertain the uurnher n' of units of volume of the bichromate solution required to complete the chloridation.Then -a (n-n') = the number of units of weight of the b bicliromate solution required to osidatc an amount of proto-chloride of tin equal to that oxidated by the nitric acid acted upon. And from the formulae hTO + 8 (SnC1 + WCl) =NH + 8SnC1 + 5H0 and K0,2Cr03 + 3SnC1 + &HC1= Cr,O + ShCL + YHO + KCl we get tlie equivalent valuc of nitric acid aid bichrornate of pt ash cxpressed by NO5 = +KO 2Cr.0 PUGH ON &4 NEW METHOD FOlt ‘L‘IiI< That is one unit of weight of bichromate of potash corrcsporids to a number of units of weight of nitric acid equal to -. NO5 ) = 0.13775 +(KO ZCrO,) KO 2Cr0 consequently if x equal the quantity of nitric acid present we have -13775 x a (n-n’) = x.b 0 8. This result is obtained without paying any regard to the atomic weight of tin; indeed the absolute quantity of tin ixsed need not be known. It is also much better to pay no regard to the atomic weight of chromic acid in fixing the strength -a of b a the solution since whatever value 8-may have the co-efficient of (n-n’) can always be reduced to a single number of 4 or at most 5 digits; and the labour of repeating a single multipli- cation for each determination is of less importance than that of getting the solutions of an exact strength to correspond with the atomic weights as is usually recommended. Besides it is of more importance in all volumetric analyses that the strength of the solutions be properly adapted to the size of the burette and the pipettes used.so that the maximum error of reading off the amount of solution required shall be inappreci- able than that they should be chosen with a view to facilitate the calculation of the result. And the latitude of this choice is too limited when confined to a multiple of so large a number as 10 as must be the case when simplicity of calculation is sought by such means. Q 9 VITe may now pass to the subject of the preparation of the reagents used. The bichromate of the shops may be used after recrystallisation and drying. The subchloride of tin may be prepared by hanging a piece of block tin or t,in foil with a platinum wire in a flask containing concentrated chlorhytkic acid.The wire should pass it few times round the tin in order by multiplicity of contact to promote the eiectro-chemical action without which the tin dissolves very slowly. A drop of bicliloride of platinum has also been recornmended to hasten the dissolution but the precipitated platinum in the solu- tion stop up the pipettes and is therefore objectionable. When so much of the tin has dissolved that it requires ahout 3 units of volume of the liichromate solution to oxidatc 1 volumc QUANTI'L'ATIVE ESTIMATION 0%'NITRIC A4<'113. of it the remaining tin may be removed by the platinum wire and the solution retained in a well-stoppered bottle for use. If the chlorhydric acid used contained either nitric acid or chlorine as the purest article of the shops always does it will have been destroyed by the tin.A weak solution of iodide of potassium free from iodate of potash must be used. As only 3 or 4 drops of a weak solutioii are used the presence of traces of iodic acid is immaterial. The starch paste or mucilage should be so thin that it Ciktl readily be drawn into a small pipette. A few miliigrammes of starch added to half a pint of' boiling water will answer. 0 10. Supposing the unit of volume to be the cubic centimetre tlie unit of weight the gramme and the diameter of the burette to be such that the maximum error of reading is less than & of this unit as was the case in my own experiments then for ordinary determinations 40 gram of the bichrornate solution may have so much water added to it that the whole shall amount to 1000 cubic centimetres.And *OPO + -13775 = 90551 grms. = NO correspondirig to 1.cc. of bichromate solution. the burette. And ~00551(n-78') = whole nitric acid in a cletermiiiation. Man&alation. 3 11. If no other substance capable of oxidating tile tin solution be present in the aqueous extract of the substance to be examined for nitric acid that extract is evaporated in a small capsule with excess of base (potash soda or lime) to as small a volume as possible. A 6 or 8 c. c. pipette is then filled with the tin solution xnd emptied into a small tube with narrow neck and funnel shaped top. (See Fig. 1.) The concentrated nitrate is brought into the saiiic tube hy means of a 1 c.c. pipette. The capsule is washed and thc wasli-ings brought into the tube in like manuer. If desirable the concentrated nitrate can be 1 ery accurately divided into two equal parts with this small pipette arid brought iirto two scparatc tabcs for duplicate analysis. PUGH ON A NEW METHOD FOR THE When ready for closing the tube should contain- 6 to 8 c. c. subchlorideof tin. 10 to 15 c. c. of nitrate and washings. 2 to 3 c. c. air below the point of closing.* This air if allowed to remain gives up its oxygen to the tin. It must be removed; this is effected by dropping a few small pieces of marble as large as a pin-head into the solution and ~10s- ing the tube after the evolution of carbonic acid gas has ceased.The tube thus prepared is placed in an oil-bath for which a small porcelain dish holding half a pint of oil will answer and the temperature is raised by a common spirit-lamp. A ther-mometer protected in a glass tube has its biilb placed in the oil to mark the temperature which to avoid danger of explosioli is read off through a small telescope. It should here be remarked however that in nearly 100 trials only three explosions took place and these were owing to the tubes being too full of fluid so that on expanding by heat the fluid filled the tube and burst it by the expansive force of water rather than that of steam. In 15 minutes the temperature may be brought to 170° and after resting 5 minutes at this point the reaction is completed.0 12. When sufficiently cooled down a drop of fluid which mostly adheres to the apex of the tube must be chased away by a gentle heat from a lamp and then the apex is broken off and the contents brought into a small beaker ;a little starch mucilage and a few drops of iodide of potassium are added and then the requisite quantity of bichromate is brought in from the burette. We thus get the value (n-n’) which multiplied by -13627 b gives the amount of nitric acid present. 0 13. The contents of the beaker may be treated with potash to alkaline reaction and then distilled till three-fourths of the fluid have gone over. The distillate may be caught in a titrated acid solution and the quantity of ammonia formed estimated from which the nitric acid present may be calculated ; or the contents * These tubes are easily made from glass tubing of the size of the largcst or-dinary combustion tnbing (+ in.diameter). The end B is closed and then ahout 5 to 6 inches up the tube it is drawn out as at 8,care being taken tEat the glass dops not liecome too thin at this point ; then after the introduction of the marble to drive out the air this neck is heated and drawn out almost to capillary fineness; 2nd the instant the marble is dissolved the tube is closed. QUANTITATIVE ESTIMATION OF NITRIC ACID. of the tube may be distilled with potash at once and the nitric acid thus determined. This method has the advantage that small quantities of other substances capable of oxidising the subchloride cannot if present affect the result.On the other hand the acids used must be free from ammonia as also must the solvent of the tin ($9) be free from nitric acid. And further when very small quantities of nitric acid are operated upon (as when the whole does not exceed -002grms.) it is not possible to determine ammonia with that extreme exactness which the above method affords in the determination of nitric acid. 0 14. Organic matters capable of oxidising the tin-solution must be removed by boiling the nitrate with permanganate of potash and then removing the excess of permanganate by carbonate of lead." Sulphuric acid was found to yield sulphurous acid but sulphate of baryta did not do so. This acid must therefore either be removed or saturated with chloride of barium.Q 15. Or no regard need be paid to these oxidising substances ; the whole may be heated as above (0 ll),and the products treated as in Q 13. Q 16. Mohr found that the oxidating value of the bichromate solution varied for different quantities of water containing equal quantities of tin; but he found that if all the air had previously been expelled from the water no suchresult was obtained. These observations of Mohr are easily confirmed; but a little care will enable the operator to use so nearly the same quantity of solution each time that the differences due to the cause just noticed will be inappreciable in ordinary determinations ;but for very small quantities of nitric acid the air must be removed. 617. Before finding that a high temperature was essential to give constant results and finding it impossible to complete the decomposition of the nitrate by the subchloride of tin and knowing that such decomposition is effected by subchloride of iron and that the perchloride of iron is reduced hy the protochloride of * Recent researches of CloEz and Guignet (Conzpt.rend. xlvii 710 1858) show that a number of nitrogeneous substances (ammonia aniline quinine cin- chonine the cyanides and sulpho-cyanides urea and gelatine as also several bodies in which hydrogen 18 replaced by hyponitric acid) give nitric ac d i\ith perman-gauate of potash. These substances may be got rid of by boiling w'th potash,-by distilling with sulphuric acid,-by destroying them with b.chromate of potash and sulphuric acid and then destroying the excess of chromiz acid with suhchlor de of tin and distilling with excess of sulphuric acid or by boiling with peroxide of manganese.My own experiments showed thit with meal from cereal and legu- rninoiis grains either fresh or partly decomposed In a so 1 no uitrate was formed by pcrmangauatc of potash. PUGH ON A NEW METIIOD kC. tin an idea was suggested that the iron might be made a means of conveying the oxygen from the nitric acid to the tin thus- NO + 6FeC1 + 3HC1 = NO + 3Fe,Cl + 3HO Fe,Cl + 2SnC1 = 2FeC1 + Sn2C1 and 2CrO + 3Sn2C1 + 3HC1 = Cr20 + 6SnC1 + 3H0 2Cr0 + 3SnC1 + 3HC1 = Cr,O + 3SnC1 + 3H0 from which a relation between the oxidating power of nitric acid and chromic acid may be obtained.But this method did not give satisfactory results when the iron and nitric acid acted on each other alone arid the tin-solution was afterwards made to act on the products thus formed and the tertiary products thus obtained were treated with the bichromate solution; nor did it when the tin and iron were acted on bothat the same time. Although the subchloride of iron alone had no power to prevent the liberation of iodine from iodide of potassium yet when mixed with the subchloride of tin this latter substance required more chromate to oxidate it than alien alone thus indicating a property in the iron subchloride to exhibit reducing forces in connection with the tin which alone were not manifested. A nitrate when ignited in a glass tube with protochloridc of tin in a current of hydrogen was found to yield ammonia; but not in sufficient quantity to indicate the possibility of obtaining a method founded upon the reaction.Nitrate of potash added to a concentrated hot aqueous solution of potash and subchloride of tin in crystals added to the mass and the whole ignited gave copious ammoniacal fumes; and several qnactitative trials by this method seemed to indicate that if suitable vessels could be obtained for igniting the mixture a good method for commercial purposes where great accuracy was not required might be obtained. But for accuracy of result the above method with sealed tubes will give results equal to those of any other dcpartment of volu-metric analysis. For those who do not like to usc sealed tubes sniall glass stoppered bottles may be used the stoppers beitig bound in by a small copper wire passing over thein and around thc neck of the bottle. In conclusion I must express my obligation to J. B. Lawes Esq. for hi! kindness in allowirig me the use of the Rothamstecl laboratory arid its ;tpparatus nucl reagents for these expcrinients.

ISSN:1743-6893    

DOI:10.1039/QJ8601200035

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

13 V1II.-New Vohtile Organic Acids of the Mountai?L Ash Berry. BY A. W. HOFMANN. WHOEVER has been engaged in the preparation of malic acid from the juice of the unripe berry of the mountain ash cannot have failed to perceive the peculiar pungent odour evolved during the evaporation of the liquid partially saturated with lime. Nobody however seems to have paid any attention to the body to which this odour belongs until my friend and former pupil lh.George Merck of Darmstadt when preparing malic acid on a large scale had the happy idea of performing the evaporation of the liquid in a distilling apparatus. He obtained in this manner an acid aqueous distillate from which an oily body of distinctly acid pro-perties could be extracted. Under the name of Vogelbeer-oel (mountain ash berry oil) a specimen of this remarkable oil was transmitted to me by Dr.Merck; and since the properties of this substance appeared of such interest as to invite a more minute examination my friend anxious to assist in the further elucidation at' this matter undertook the preparation of a larger quantity of the oil. To his kindness I owe the whole of the material em-ployed in the experiments which I am going to describe. I have received from Dr. Merck the following account of the process by which he has produced the new oil :-The juice of the unripe berries had been boiled with a quantity of milk of lime insufficient for the saturation of the acid which it contained and the solution on cooling had deposited the bimalate of calcium.The liquid separated from the crystals mas int'roiluced into a copper still and distilled over an open fire. The condensed vapours furnished a powerfully acid distillate and when after some time the acid reaction of the liquid which distilled over ceased it could be renewed by pouring a quantity of dilate sulphuric acid into the still. In order to coiicentratc the acid the aqueous dis-tillate was saturated with carbonate of sodium and evaporatcd on the water bath. The residuary semi-solid mass was decomposed in a tall glass cylinder by moderately concentrated sulphuric acid vrhen tlle oil rose as abrown layer on the surface of thc colourleas saline solution. It was dissolved in cther separated €IV~Ithe IIOFMANN ON NEW aqueous liquid and reetified after the ether had been allowed to evaporate.Several specimens of the mountain ash-berry oil which Dr. Merck had prepared at different periods exhibited some discre-pancies in their properties. Several were of mobile fluidity and scarcely coloured ; others brown nearly black and considerably resinified. On rectification however the oil was Obtained colour- less. Ebullition commenced at a temperature but little higher than 100°C; the distillate at this stage of the operation separated into two layers,- oil which still contained \.T ater floating upon an aqueous solution of the acid. On continuing the distillation the temperature rose rapidly to 20OoC then more slowly until it reached 225°C. There remained in the retort more or less of a yellowish brown transparent resinous matter.A few distillations soon convinced me that by far the greater bulk of the oil consists of a homogeneous substance which is however very apt to change under various influences. Freshly distilled the mountain ash-berry oil constitutes a trans- parent colourless liquid of a peculiar aromatic odour not unplea- sant when dilute but rather disagreeable and almost overpowering when concentrated. The oil has a sp. gr. 1,0681 and boils con- stantly at 221OC under a pressure of 0.755 m. It is appreciably soluble in water soluble in all proportions in alcohol and ether. Thc solutions are strongly acid. The mountain ash-berry oil has the characters of an acid. It dissolves with facility in the fixed caustic alkalies and in ammonia also in baryta-and lime-water.Even in carbonate of sodium the oil dissolves without however expelling the carbonic acid. The solutions thus obtained yield on evaporation dry resinous residues which indicate no signs of cry stallisation. Addition of hydro-chloric acid to these residues separates the original oil unchanged. The ammonia-solution furnishes with nitrate of silver a white gelatinous precipitate which slightly changes colour when exposed to the light. 'I'wo combustions of the oil gave the following results :-I 0.2280grm. oil gave 0.5352 grrn. carbonic acid and 0.1449 grm. water. II. 0.1926 grrn. oil gavc 0.4546 grm. carboriic acid arid 0.1280 grm. water. 45 In the analysis of the silver-compound just mentioned- 0.2465 grrn.silver-salt left 0.1209 grm. silver. The simplest expression for the acid suggested by these data is the formula- C 2HB04J the theoretical values of' which I subjoin with the experimental percentages. Theory. Experiment. Mean 12 equiv. of Carbon 72 64.28 64.01 64-27 64.14 8 , Hydrogen 8 7-14 7.06 7-38 7-22 4 , Oxygen 32 28.58 28.93 28.35 28.64 --_^__-1 equiv. of Oil 112 100~00 100~00100~00 100*00 In the silver-compound one equivalent of hydrogen of the acid is replaced by one equivalent of silver. The formula is supported by the silver-determination above quoted Theory. Experiment Percentage of Silver 49-31 49-05 I should have endeavoured to obtain additional compounds of the oil in order to gain if possible further data in favour of the formula which I propose had not any effort in that direction become superfluous by the observation of the remarkable deport- ment of the oily acid under the influence of powerful bases and acids.I have stated that the solution of the oil in potassa furnishes on addition of a mineral acid the unchanged oily acid; the alkaline solution may even be boiled for some time without altering the nature of the substance. But on gently heating the oily acid with solid hydrate of potassa an unexpected transformation takes place. The product of the reaction dissolved in water and saturated with hydrochloric acid furnishes an oil which rapidly solidifies into a hard crystallhe compound possessing the characters of a well defined acid.This observation at once suggested the idea of alde-hyde and acid but it was found that the transformation takes place without the evolution of a trace of hydrogen. Several grammes of the oil were heated for two or three hours in a sealed tube with hydrate of potassa in a water-bath. Not a trace of gas was clis. engaged when after cooling the tube was opened under water but the oil mas almost entirely converted into the crystalline acid. The same molecular transformation as might have been expected is produced by the action of acids. On boiling the oil for a short time with concentrated hydrochloric acid it becomes more and more viscid and ultimately solidifies. A similar result is produced by sulphuric acid.The oily acid dissolves in concentrated sulphuric acid the oil which is reprecipitated by addition of water gradually becomes a solid crystalline mass. The mode of forming the new acid suggested the probability of its being isomeric with theoriginal oil. This suggestion has been fdy borne out by experiment. I propose to designate this beau- tiful body by the name of sorbic acid reviving thus a name once used for malic acid. The oily acid may then conveniently be called parasorbic acid; for although more directly related to the moun-tain ash its character is less defined and salient than that of its derivative. Sorbic acid is readily purified ; being nearly insoluble in cold and moderately soluble in boiling water this substance is chemi- cally pure after two or three crystallisations from boiling water.It dissolves with great facility in alcohol or ether. The most appropriate solvent is a mixture of 1vol. of alcohol and 2 vol. of water. From this liquid the acid separates on cooling in magni- ficent white needles often several inches in length. Sorbic acid is inodorous. When in contact with a quantity of water insufficient for its solution the acid fuses at the temperature of boiling water. The fusing point of dry sorbic acid is 134.5OC; at a higher tern. perature the acid distils without decomposition. Sorbic acid is a powerful acid expelling carbonic acid from all the carbonates. The composition of sorbic acid was fixed by the following experiments :-For experiment I. the acid had been dried over sulphuric acid for experiments 11.and 111.in the water-bath.I. 0.3331 grm sorbic acid gave 0.7877 grm. carbonic acid and 0*2160grm. water 11. 0.4065 grm. sorbic acid gave 0.9561 grm. carbonic acid and 05?705 grm. water. 111. 0.3593 grm. sorbic acid gave 0%600 grm. carbonic acid and 0.2264grm. water These results lead to the formula previously established for parasorbic acid. Theory. Experiment Mean. I. 11. 111. 12 eq. of Carbon 72 64.28 64-49 64-14! 64.51 64-38 8 , Hydrogen 8 7.14 7.20 7*39 7-00 7.20 4 7 Oxygen 32 28-58 28.31 28.47 28.49 28.42 1 eq. of Sorbic Acid 112 100.00 100.00 100*00 200.00 100*00 The composition of sorbic acid receives additional support from the analysis of several of its salts and derivatives.Sor6ate of SiZver. White insoluble pulverulent precipitate obtained on adding nitrate of silver to sorbate of ammonium. I. 0.6288grm. silver-salt gave 0.7488 grrn. carbonic acid and 0.1807 grm. water. 11. 0.4635 grm. silver-salt gave 0.3012 grm. chloride of silver. 111. 0.6546 grm. silver-salt gave 0.4275 grm. chloride of silver. To the formula Cl [H,*glO* correspond the following values :-Theory. Experiment. I. XI. JI I. 12 equiv. of Carbon 72 32-88 32-48 - - 7 , Hydrogen 7 3-19 3.19 - - 1 , Silver 108 49*31 - 48.90 49.15 4 - 9 Oxygea 32 14.62 - 3 - 1 ey. of Silver-salt 219 lo000 Sorbate of Barium. On boiling carbonate of barium with an aqueous solution of sorbic acid a neutral solution of the barium- compound is obtained which yields a crystalline residue on IIOFMANN ON NEIV evaporation.The salt is not much less soluble in cold than in boiling water. It is however less soluble in alcohol. The best mode of obtaining it in the pure state consists in adding alcohol to the boiling aqueous solution; on cooling the sorbate of barium crystallises in scales of silver-white lustre. The salt is anhydrous. I. 0.4144 grm. of sorbate of barium dried at 125" C. gave 0.6135 grm. of carbonic acid and 0.1502 grm. of water. 11. 0.2863grm. of sorbate of barium treated with sulphuric acid left 0.1846 grm. sulphate of barium. The formula Cn [H,BalO requires Theory. Experiment. I. TI. 12 equiv. of Carbon 72 40.11 40.37 -7 , Hydrogen 7 3-90 4.02 -1 , Barium 68.5 38.16 -37.89 4 > Oxygen 32 17.83 -1 eq.of Barium-salt 179.5 100.00 Xorbate of CaZcium. Preparation and properties perfectly similar to those of the preceding salt. The formula was controlled by a calcium-determination. 0.2463 grm. of the salt dried at lMoC. and treated with sulphuric acid left 0.1260 grm. sulphate of calcium. Theory. Experiment. Percentage of Calcium 15.26 15.05 I have not analysed any of the other metallic sorbates; but have made some qualitative observations which may be recorded as contributions to the history of the acid. The sorbates of potassium and of sodium arc very solixhle salts crystallisirig with difficulty ; the ammonium-compound is likewise very soluble but crystallises beautifully in long slender needles which are apt to lose part of the ammonia by exposure to the air.A concentrated solution of the ammonium-compound shows the following deportment with reagents Chloride of calcium . White crystalline precipitate appearing after a short time. Chloride of barium Chloride of strontium No precipitate. Chloridc of magnesium 11 Aluminium -alum . . White precipitate which dissolves in ether and is therefore nothing but the acid. On ebullition a precipitatc is formed which is insoluble in ether and is probably the sorbate. Chromium-alum . . White precipitate of the acid. On ebullition a green amorphous preci- pitate of sorbate of chromium. Sulphate of iron . . Yellowish dingy amorphous precipi- tate.Iron-alum . . Yellow amorphous precipitate. Sulphate of nickel . . Greenish amorphous precipitate. Nitrate of cobalt . . No precipitate. Sulphate of manganese . Granular crystalline white precipitate appearing after a few minutes. Sulphate of zinc . . White acicular precipitate which ap- pears after a short time. Insoluble in ether. Acetate of lead . Nitrate of mercury curosum) . White copious amorphous precipitate. Chloride of (Mercuricum) . Sulphate of copper. Light bluish green amorphous precipi- tate. The analytical results obtained in the analyses of the acid itself and of the silver- barium- and calcium-compounds are sufficient to VOL XII. E HOFMANN ON NEW cstshlish the conipositioii of sorbic acid. It remttiiiq now bi~t twiefly to mention a few cvyerimcnts miiadc respecting the deriva- tives of sorbic acid; they are rather fi-agmentsry but may serve to complete the picture of the acid.Sorbic ether.-Colourless liquid boiling at 195.5' C. lighter than water possessing an aromatic oclour similar to that of benzoic ether. It is conveniently obtained by saturating the alcoholic solution of the acid with dry hydrochloric gas. The action of chloride of sorbyl upon alcohol produces the same compound. Sorbatc of ethyl contains C16H1204 = Cl C~~,(C*H,)IO* as proved by the combustion of the ether. 0.2136 grm. of sorbic ether gave 0.5342 grm. of carbonic acid and 0.1644grm. of water. Theory. Experiment. 16 eyuiv. of Carbon . 96 68.5'7 68.21 12 4 , , Hydrogen Oxygen .. 12 32 8.57 22.86 8.55 - - __I- 1 , Sorbic Ether 140 100.00 Chloride of Sorbyl is obtained by the usual processes; by the action of pentachloride of phosphorus upon the acid or of the trichloride upon the potassium-compound. The limited amount of acid at my disposal did not permit me to procure this substance in a state of purity and to establish analytically the formula (C12W2) c1 assigned to it by theory. But this formula is indirectly proved by the deportment of the crude product still containing chloride of phosphorus with water,-when sorbic acid is at once reproduced,- with alcohol,-when sorbic ether is obtained,-vith ammonia and phenylamine,-when respectively sorbamide and phenyl-sorbamide are generated. The chloride is not volatile without considerable decomposition.Sorbamide.-This substance is formed by the action of dry car- bonate of ammonium upon the crude chloride. It is also pro-duced by digesting sorbic ether with aqueous ammonia in a sealed tribe at a temperature of 120°C. At too high a temperature however or by protracted digestion the amide absorbs the ele- ments of water and regenerates sorbate of ammonium. Sor- VOLATILE ORGANLC ACIDS kC. bainidc forms white readily fusible needles soluble in water and in alcohol. I liad scarcely a sufficient quantity for analysis at my disposal but the following numbers although exhibiting a slight deficiency in hydrogen establish the composition of sorbamide 0.0942 grm. of' sorbamide gave 0*2230grm of carbonic acid and 0.0665 grm.of water. The formula C,,H9N02 = H requires Theory. Experiment. 12 equiv. of Carbon . 72 64.86 64.55 9 , Hydrogen . 9 8-10 7.84 i , Nitrogen . 14 12.61 -2 , Oxygen . 16 14.43 -1 , Sorbamide 111 100*00 Phenyl-sorbamide (Sorbanilide) is obtained by replacing the am- monia in the previous process by phenylamine. After treatment ~bith water an oily liquid remains which gradually soliciifies into a crystalline mass. I have not analysed it its composition being sufficiently characterised by theory. When distilled with an excess of hydrate of baryta sorbic acid cxhibits the deportment of the acids with 4 equivalents of oxygen; carbonate of barium being produced whilst an aromatic hydro- carbon distils over.The limited amount of material has pre- cluded for the present the possibility of a more minute examina- tion of this body. Sorbic acid is obviously the first term of a new series of well characterised organic acids closely allied with the ordinary fatty arid aromatic acids occupying in fact a sort of intermediate position between the two. On comparing sorbic acid with the terms of the fatty and aromatic acid series containing an equal number of carbon-equivalents the hydrogen of sorbic acid stands in the middle C12H 1204 c,$804 C12H404 Caproic acid. Sorbic acid. Lox er homologue of Benzoic acid. E% BARRAT AiYAT,YSIS OF THE The same remark applies to the carbon if sorbic acid l)c COH-. trasted with the fatty and aromatic acids containing an cqiial number of hydrogen-equivalents C8H804 C,,HP4 C16H804 Butyric acid. Sorbic acid. Toluic acid.

ISSN:1743-6893    

DOI:10.1039/QJ8601200043

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

J3ARRA'I' AiYAT,YSIS OF THE IX.-Analysis of the Water of Holywell North Wales BY JAMESIhRILAT STUDENT IN THE LIVBRPOOL COLLEGE OF CHEMTSTRY. THEwell of St. Winifred at Holywell has long been noted for its salubrious qualities. There is however nothing remarkable in its composition as regards either the quantity or the quality of the substances dissolved in it excepting perhaps its freedom from organic matter; so that the salutary effects said to follow its use ought perhaps to be attributed rather to the healthiness of the locality than to any specific action of the water. The following are the results of the author's examination Temperature of the water 52' Fahr. Specific gravity of the water 1.0016. The qualitative analysis pointed out the presence of soda lime magnesia chlorine carbonic sulphuric and silicic acid.Traces of potash aud iron were detected on evaporating a very large quantity of the water but they were too minute for estimation. The residue obtained by evaporating thrse gallons of the water did not exhibit the slightest traces of iodine bromine or fluorine. Determination of the total amount of fixed constituents :-Amount of water employed. Amount of residue obtained. Per imperial gallon. 20*000grs. 8.700 grs. 30-450grs. Determination of chlorine- Amount of water employed. Amount of chloride of silver obtained. Per imperial gallon. 20.000grs. 2.9973 2595 grs. Determination of sulphuric acid- Amount of water employed. Amount of sulphateof baryta obtained. Per imperialgallon.20.000grs. 2-5473 3.060 gl's WAlER OF HOLYWELL. Determination of silicic acid- Amount of Amount of ailicic Per imperial water employed. acid obtained. gallon. 20*000grs. -782 2.737 grs. Uctermination of lime and mzgnesia- Amount of Amount of carbonate Per imperial water employed. of 1 me obtained. gallon. 90*000grs. 6.546 10.367 grs. Determination of rnaguesia in the filtrate from oxalatc of lime-Amount of Amount of pyrophosphabc Per imperial water employed of magnesia. gallon. 20.000 grs *YYO 1.242 grs. l)e termination of soda-Amount of Amount of chloride of Per imperial water employed. sodium obtained. gallon. 20.000 grs. 700 2.450 grs. Determination of carbonic acid- Two lialf' gallon bottles 11 ere filled with tlic water and chloride of calcium and arnrtionia were added-Amount of carbonic acid ex-olved.Per imperial gallon 9.145 grs. 18.310 grs. X;lopting the usnd arrangcmcut of corlibining the acids and ba%esaccording to their supposcd clmiiicul affiuities the following tabulated form is obtained :-Per imperial gallon (grains). Carbonate of lime . 13.683 Carbonate of magucbin . 2'.688 PI otocarbouate of 11oir . traces Sulyhate of 11me . 5.202 Ctllor.,ctc of sodlunl . -851 Chiode d potassium . traces Chloride of calcium . 3.094 Carbonate of soda . 1.432 Sulylrate of magucsia . traces Silicic acid . 2-737 29.689 Direct dctermiir;Aon of fixcd coristituurits 30.460 GILBERT ON Deducting from the total amount of carbonic acid the portion in combination with lime magnesia and soda the quantity of free carbonic acid amounts to 10.338 grains corresponding to 21.87’4 cubic inches in the imperial gallon.

ISSN:1743-6893    

DOI:10.1039/QJ8601200052

出版商:RSC    

年代:1860

数据来源: RSC

摘要:

GILBERT ON X.-Discourse :-On the Composition of the Animal Portion of our Food and on its Relations to Bread. BY J. H. GILBERT, Ph. D. F.C.S. (Abstract). IT has been pretty generally maintained that the comparative values of our stock-foods as such are determinable chiefly by the proportion of nitrogenous constituents which they contain. The results of experiments on the “feeding” or I‘ fattening” of animals for the purpose of human food do not bear out this conclusion. It has been further pretty generally assumed that in the admixture of animal food with our otherwise chiefly farinaceous diet the nitro- genous or so-called ‘(flesh-forming constituents,” are increased in their proportion to the more purely respiratory and fat-forming capacity of the food.It was submitted that such an explanation of the benefits derived by the admixture of our animal with our staple vegetable aliments is not admissible. The experimental data upon which the Discourse was founded had been collected by Mr. Lawes and Dr. Gilbert in the course of a lengthened inquiry,* the main objects of which had been to determine with a view to the agricultural bearings of the subject the relations of the constituents consumed in the food of fattening animals to those stored up in their bodies as increase on the one hand and to those voided as manure on the other. So far how-ever as the composition of the animals was adequately determined for the purposes of such an inquiry the results mould also afford some insight into the characters and composition of the food sup-plied to man in the bodies of the fed and slaughtered animals.The average composition of wheat-flour bread had also been carefully determined. The means of comparing with one another our staple animal and vegetable foods mere thus at command. The weights of the carcases arid of the several internal organs and other separated parts had becn determined in the case of * See “ Experimental Inquiry into the Composition of some of the Animals fed and Slaughtered as Humin I”ood.”-By J. 13. Lawes Esq. F.R.S. and J. H. Gilbert Ph. D. -Proceedings of the Royal Society) 1’01. ix. p. 348 ; and for full details- ‘‘The Transactioas of the Royal Society ” ANIMAL FOOD IN RELATION TO BREAD. several hundred animals-bullocks sheep and pigs-which were selected for slaughtering in different conditions of maturity and fatness.It appeared that whilst the internal organs-or so to speak the machinery employed in the production of the meat-- iucreased considerably in actual weight during the “feeding” or “fattening” period yet they diminished in proportional amount to the whole body or to the carcase. That is to say it was the carcase-the most important edible portion-that increased the most rapidly. To ascertain more exactly the composition of our slaughtered animals and of their increase whilst fattening 10 animals of dif- fcrent descriptions and in different conditions of maturity had been devoted. In these the amounts of water mineral matter nitrogenous substance and fat had been determined; (1) in the entire carcases; (2) in the collective “offal” parts; (3) in the entire bodies.The results showed that the largest item in the dry or solid substance of the animal bodies was fat ;and that by far thc largest proportion of that in the whole bodies was found in thc carcase parts. The carcases of well-fattened animals (those of calves excepted) appeared to consist of fat to the extent of from one-third to one-half of their entire weight. The percentage of‘ fat in both carcase and offal parts but especially in the former increased very considerably during the feeding period whilst that of the nitrogenous substance diminished. Excluding the calf the entire bodies in a condition of fatness fit for human food consisted of about one-third and sometimes of considerably more thau one- third of pure dry fat.The dry nitrogenous substance on the other hand even including that of the wool in the case of the sheep amounted to less than one-half and sometinies to less than one-third as much as the dry fat. Applying the results to calculate the composition of the increase of animals liberally fed on fattening food it appeared that this would probably consist of nearly three-fourths dry solid substance. Little less than two-thirds of the gross increase of highly fed aiiimals would be far itself; and 6 to 8 or 9 per cent. only dry nitrogenous substance. It was calculated that frequently iiot more than 5 and seldom if ever as much as 10 per cent. of tlie nit rogcnoua substance of the fattening food would be finally stored up in the increase of the animal.In some cases of experi-ments with pigs it was cstirnated that more than 4 tirncs as much fat tiad heen stored up iii the increase as had liecr supplied ready GILBERT ON formed in .the food. Three-fourths of the fat of the increase had therefore been produced from other constituents of the food. If starch were the source of this produced fat it would require about 23 parts of that substance for the production of 1 part of fat. The general conclusions mere-that but a small proportion of the increase of a fattening animal was nitrogenous substance ;that less than 10 per cent. and even as little as 5 per cent. of the nitrogenous substance of good fattening food would probably be finally stored up in the increase ; that the proportion of fat stored up was very much greater than that of nitrogenous substance; and lastly that the stored up fat would frequently involve in its production an amount of the non-nitrogenous constituents of the food much greater than the weight of the stored up fat itself.When in addition to these facts it was remembered how great would be the demands upon the non-nitrogenous constituents of the food for the maintenance of the respiratory process it need hardly excite surprise-that the comparative values of fattening foods as such seemed to be determinable more by their proportion of digestible or available non-nitrogenous than by that of their nitrogenous or assumed flesh-forming constituents.Accordingly numerous experiments with staple fattening food-stuffs Bad shown that both the rate of consumption for a given weight of animal within a given time and the amount of increase in weight pro- duced had a much closer connection with the amount of non-nitrogenous or of total dry organic constituents than with that of the nitrogenous constituents in the food supplied. This was strikingly the case when our ordinary cereal grains and leguminous seeds were compared with one another on the points in question. It remained to compare our staple animal foods (produced and composed as above described) with our most important vegetable ali- ment-bread in relation to the proportion in each of theJle,..h-form- ing to the respiratory and fat-$orrning capacity.From a careful consideration of what portions of the fattened animals would be on the average consumed it was estimated that in thc so-applied parts of oxen thcre would be from 2 to 3 timcs arid in those of lambs sheep and pigs frequently more than 4 timcs as much dry- fat as dry nitrogenous substance. According to the numerous resultsof Drs. Watson and Odling and of Mr. Lawes and Dr. Gilbert wheat-$our lweacl was reckoned to contain from 6 to 7 parts of noii-nitrogermis to 1 of iiitrogciious substancc. It might ANIMAL FOOD 1N RELATION TO BREAD. be assumed that in a certain broad yet at the same time ad- mittedly qualified sense 1part of fat was equal to 2+ parts of the starch and other non-nitrogenous matters in bread in point of respiratory and fat-forming capacity.Adopting this assumption it appeared that in the consumed portions of well-fattened oxen the relation of the respiratory and fat-forming to the flesh-forming capacity would be about the same and in those of well-fattened lambs sheep and pigs about 1+ times as high as in the staple vegetable food-wheat-$our bread. Were it granted that the pro- portion of the whole fat of the slaughtered animals which was sup-posed to be consumed was too high it must on the other hand be remembered that the nitrogenous substance would contain a con- siderable proportion of gelatigenous matter the applicability of which for flesh-forming mas to say the least doubted. It ap-peared therefore so far as chemical inquiry of the kind in ques- tion was competent to throw light on the point that on the large scale the introduction of animal aliments into our otherwise chiefly farinaceous diet did not increase but diminish the relation of the so-called flesh-forming to the respiratory and fat-forming capacity of the collective food. It remained then for physiology yet to providc the true explanation of the admitted benefits arising from thc admixture of animal food with bread.

ISSN:1743-6893    

DOI:10.1039/QJ8601200054

出版商:RSC    

年代:1860

数据来源: RSC