摘要:

THE QUARTERLY JOURNAL OF THE CHEMICAL SOCIETY OF LONDON LONDON HIPPOLYTE BAILLIERE 219 REGENT STREET AND 290 BROADWAY NEW YORK U.S. PARIS J. B. BAILLIERE RUE HAUTEFEUILLE MADRID BAILLY BAIZfiIERE CALLE DEL PRINCIPE. 1859. LONDOK PRINTED BY HARRISON AND SONS ST. MARTIN’S LANE w c. CONTENTS OF THX ELEVENTH VOLUME. PAGE Xote on Rosolic Acid. By Dr. Hugo Miiller ........................................ 1 On the Arseniates of Baryta Lime and Magnesia and the Separation of Arsenic from other Elements. By Frederick Field M.R.I.A. F.C.S. ...... 6 On the existence of a Second Crystallizable Fluorescent Substance (Paviin) in the Bark of the Horse-Chestnut. By Q. Q. Stokes M.A. Sec. R.S. &c.17 On the Action of Bromine on Acetic Acid. By W. H. Perkin F.C.S. and B. F. Duppa Esq. .................................................................. 22 On the Use of Gas as Fuel in Organic Analysis. By A. W. Hofmann ............ 30 On the Chemical Action of Water on Soluble Salts. By Dr. J. H. Gladstone F.R.S ....................................................................................... 36 Proceedings at the Xeetings of the Chemical Society ................................ 50 On aome Compounds of Iodide and Bromide of Mercury with the Alkaloids. By Thomas B. Groves F.C.S. Weymouth .......................................... 97 On a new method of preparing Propionic Acid viz. by the action of Carbonic Acid upon an Ethyl-compound.By J. A. Wanklyn Esq. ..................... 103 Notice of another New Xaximum and Minimum Mercurial Thermometer. ByJohn Q. Macvicar D.D. Moffat ..................................................... 106 On the Atomic Weights of Oxygen and Water. By William Odling M.B. Secretary to the Chemical Society .................................................. 107 On the General Character8 of the Iodo-Sulphates of the Cinchona-Slkaloida. By W. Bird Herapath M.D. F.R.S.E. ............................................ 130 Some remarks on Poison obtained from Arrows. By Henry J. B. Hancock Esq. 154 On the Composition and Analysis of Black Ash or Ball Soda. By Josiah W. Kynaston Esq. Student in the Liverpool College of Chemistry............... 155 Process for the quantitative estimation of Sulphides Sulphites Hyposulphites and Sulphates in presence of each other as adopted in the determination of these Salts in “Soda Waste,” as obtained from “Black Ash.” By J. W. Kynaston Esq. Student in the Liverpool College of Chemistry ..... 166

ISSN:1743-6893    

DOI:10.1039/QJ85911FP001

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

6 11.-On the Arseniates of Baryta Lime and Magnesia and the Separation of Arsenic porn other Elemeds. BY FREEERICK FIELD,M.R.I.A. F.C.S. ALLchemists must have experienced the difficulty of separating arsenic from other elements with whichbit is associated. It is scarcely necessary to say that the method usually adopted is to precipitate the arsenic as sulphide with the other metals which are thrown down by sulphide of hydrogen from their acid solutions and subsequently digest the precipitate with the sulphides of ammonium or potassiiim. Many other bodies however are re- dissolved as well as the sulphide of arsenic the separation of which in this stage of the process becomes exceedingly perplexing and difficidt. Even in the earlier operations of the analysis the arsenic has to be entirely converted from arsenic acid into arsenious acid in order to insure its entire precipitation and this is usually effected by sulphurous acid or a sulphite.When tEe arsenic exists in a very large proportion repeated deoxidations and precipitations are necessary which not only involve the expendi- ture of much time and labour but are attended with loss of the substance under aiialysis. Much of the arsenic it is true can be eliminated by calcination with occasional additions of carbon ;and probably in the establishments where nickel and cobalt are obtained on a large scale eight or nine-tenths of the arsenic are got rid of by this method. Even then the manipulator finds it necessary to pass a powerful and long-continued stream of sul-phuretted hydrogen through the solution of the oxides and to expel the excess by ebullition previous to the separation of iron nickel and cobalt.Calcination however is inadmissible in chemical analysis for-independently of the mechanical loss which is likely to occur-some metals especially silver are volatile in arsenical fumes. Moreover presuming that all the operations mentioned above have been carried out successfully the arsenic cannot be separated entirely by the alkaline sulphides. Mr. Bloxam has shown" that Then the proportion of copper is large * Quarterly Journal of the Chemical Society vol. v p. 104. ARSENIATES OF LIME BARYTA AND MAGNESIA.. much arsenic is left with its sulphide even after long digestion with sulphide of ammonium and indeed that 1 per cent.of arsenic becomes insoluble iii the alkaline sulphide when the remainder consists of sulphide of copper. In the analysis of the ores of nickel and cobalt I have found the formation of arseniate of potash highly useful as a means of separating arsenic from these metals. When the arseniates of nickel and cobalt in solution of hydrochloric acid are boiled with excess of potash they are entirely decomposed the whole of the arsenic wid uniting with the alkali. Ammonia cannot be employed as the arseuiate of nickel is very slowly decomposed by this reagent. When native arseniate of nickel is dissolved in hydrochloric acid and ammonia added a gelatinous white precipitate is produced and the super- natant liquid is colourless; and in order to obtain the blue ammo- niacal solution it is first necessary to free the nickel from arsenic.Iron is also present in this class of minerals and sesqui-arseniate of iron is highly soluble in ammonia so that if the substance con- tain arsenic it is impossible to separate nickel from iron by that alkali. When an ars&cal ore of cobalt (containing iron) is digested in nitro-hydrochloric acid and ammonia added in excess no precipitate is formed provided there be sufficient arsenic to convert the whole of the iron into arseniate and chloride of ammo-nium to form a soluble compound with cobalt. The solution has a fine brown colour and is decomposed by sulphate of magnesia sesquioxide of iron and ammonio-arseniate of magnesia being formed.When only iron and arsenic are present both are preci- pitated in this manner and the supernatant liquid contains merely ammoniacal salts. The employment of sulphate of magnesia in conjunction with ammonia for the determination of arsenic acid has been pro- posed by Level;* and Rose in his Handbook of quantitative analysis strongly recommends this process as very accurate yro-vided certain precautions are adopted in preparing the arseniate of magnesia and ammonia for the determination of its weight. Rose also applies this method to the separation of arsenicfrom antimony and states that it is the best process known furnishing very accurate results if conducted with care. I was led in the first instance without previous acquaintance with the results of Levol and Rose to institute experiments with a view to the application of magnesia to the determination * Ann.Ch. Phys, [3] xvii 501. FIELD ON THE of arseaic in the above manner and to submit to a comparative examination the precipitates produced by baryta lime and msg-nesia in an ammoniacal solution of arsenic acid for the purpose of ascertaining the relative values of the alkaline earths in this branch of analysis. The present communication contains a sum-mary of these experiments Arseniate ofBaryta.-When chloride of barium is added to a solution of arsenic acid in ammonia the latter being in excess a copious precipitate of trisarseniate of baryta is formed consisting of 3Ba0,As05. According to Graham this substance attracts a small quantity of carbonic acid from the air.B er z eliu s says it is very slightly soluble in water somewhat more soluble in aqueous ammonia; and Laugier informs us that the solubility does not seem to be increased by the presence of ammonia potash or soda salts.* My own experiments differ considerably fiorn the above. The arseniate of baryta was found to consist after very careful analysis of- Baryta . . 66.39 Arsenic Acid 33.32 99*71 or 3BaO,AsO Calculated. 3Ba0 . . 66.65 Arsenic Acid 33.35 100~00 The baryta was precipitated from the solution of the arseniate in hydrochloric acid by sulphate of soda. After deoxidation by sulphurous acid the arsenic was estimated as tersulphide-10.00grs.3BaO,AsO,= 6.639 BaO and 3.55 ASS,-3-33AsO,.10*00grs. arsenious acid were converted into arsenic acid and ammonia added in excess. The addition of chloride of barium caused a precipitate which after washing with weak ammonia until no chlorine could be detected in the filtrate gave on desicca- tion at 300’ Fahr.-34.52 grs. 3BaO,AsO,. 34*57grs 3BaO,AsO,. Calculated. Arseniate of baryta loses all its water at a temperature a little above 212O. After diying in a water-bath for several hours 18.90 grs. only lost 0.05 on ignition. After drying upon a sand- * Gmelin’s Handbook vol. iv 304. ARSENIATES OF LIME BARYTA AND MAGNESIA. bath at a temperature which never exceeded 300°,in a platinum crucible no loss was experienced on heating to redness.With regard to the solubility of this salt the following experi- ments were performed 10-00grs. 3BaO,AsO digested with 2000 grs. cold distilled water for forty-eight hours lost 1-10gr. The filtrate gave 0*9gr. sulphate of baryta on addition of sulphate of baryta. 10.00id.digestedwith 2000gru. solution of chloride of ammonium (containing 100 grs. ofthe dry salt) lost 39352. The filtrate gave 341 sulphate of baryta. 10.00id. digested with solution of ammonia formed by adding 200 grs. ammonia sp. gr. *880 to 1800 grs. water lost 0.06. Sulphate of soda hardly produced any precipitate of sulphate of baryta in the filtrate. From this it appears that although very soluble in chloride of ammonium and moderately so in water arseniate of baryta is very insoluble in aqueous ammonia And even (as in most cases in analysis) when chloride of ammonium is present the addition of excess of ammonia prevents in a great measure the solubility of the baryta salt.And it may be mentioned here that ammonia determines the insolubility both of the magnesia and lime arseniates in the same manner precipitating the ammonio-arseniates from their solution in chloride of ammonium Chloride of barium can be advantageously employed for the detection of small quantities of arsenic acid when in combination with copper and other metals. 100*@0 grs. of copper free from sulphur were placed in a flask together with 0'20 grs. arsenious acid. After solution in nitric acid and addition of excess of ammonia sulphate of magnesia caused a precipitate which settled at the bottom of the vessel after 12 hours.On filtering the small precipitate arsenic was readily detected by the usual test. Minerals containing sulphur arsenic and nickel can be very neatly and correctly analysed by the employment of a baryta salt. By adding chloride of barium in excess to the acid solution sulphate of baryta is precipitated and after filtra-tion and addition of a large excess of ammonia all the arsenic is precipitated provided sufficient chloride of barium has been employed. It is necessary to add this reagent to the acid solution and therefore to decompose the arseniate of nickel in hydro- chloric acid. There is no fear of any nickel remaining with the FIELD ON THE mseniate of baryta which is a dense white powder and can be thoroughly and expeditiously washed.For this purpose of course tt weak solution of ammonia is employed instead of pure water. Arseniate of Lime and Ammonia.-When diarseniate of am-monia potash or soda is added to a solution of chloride of calcium trisarseniate of lime is formed and the supernatant liquid becomes acid. When chloride of ammonium trisarseniate of ammonia and lime-water are mixed together crystals of arseniate of ammonia and lime 2CaO,NH,O,AsO are found." I have met with two distinct precipitates during the course of my experiments which possessed the following characteristics 10.00 grs. arsenious acid were converted into arsenic acid ammonia added in very slight excess and subsequently solution of chloride of calcium.The precipitate after prolonged washing with water and dessication at 300° weighed 15.50 grs. and on ignition lost only 0*80gr. yielding 14-70of a compound of arsenic acid and lime. A large quantity of arsenic was detected in the filtrate. 10.00 grs. of arsenious acid were similarly treated and the preci- pitate washed with weak ammonia; after drying at 300° it was found to weigh 18*24grains and 17.02 on ignition. The precipi- tates in both instances seemed to consist of different substances one of a very slightly crystalline powder the other of tolerably large needles united together in stellated masses. Although in the latter experiment the 10 grs. of arsenious acid yielded 17.02 of lime salt and by calculation it should yield 17-10 diarseniate of lime (2CaO,AsO,) the loss by ignition was so small and so much less than it would have been had an atom of ammonia been expelled as to lead me to doubt very much if the precipitate were the arseniate of lime and ammonia notwithstanding that it evolved much ammonia on ebullition with potash.In order to analyze the residue left upon ignition advantage was taken of the fact that arseniate of lime is perfectly decom- posed by a boiling solution of oxalate of ammonia. It is better however to dissolve the arseniate in hydrochloric acid add the oxslate and finally excess of ammonia and boil for some time. The whole of the arseniate is found in the filtrate and the lime in the precipitate as oxalate of lime.The 14.70 grains boiled in this manner gave on ignition 8.00 carbonate of lime= 5.48 lime and the 17-02 grs. gave it Gmdin's Handbook vol. iv p. 304. ARSENIATES OF LIME BARYTA AND MAGNESIA. 1lW56CaO,CO,= 6.47 CaO. Sulphate of magnesia was added to the filtrate and after standing some time the ammonio-mapesian ameniate collected and the arsenic estimated. Composition of Diarseniate of Lime 2CaO,AsO Lime Salt Calculated. Found. Lime . . 4.82 Lime . . 5-48 Arsenic Acid 9-88 Arsenic Acid 9.27 14.70 14-75 Lime . . 5-57 Lime . . 6.47 Arsenic Acid 11.45 Arsenic Acid 10.44 17.02 16.91 It is evident from the above analyses that the salt under con-sideration is not diarseniate of lime but probably a mixture of diarseniate and triarseniate the former produced by the decom- position of the ammonia compound thrown down from the original solution in company with the triarseniate.The loss by ignition as well as the quantities found of arsmic acid and lime leave no doubt that this is the case. 3Ca0 As05+2Ca0 NH,0,As05 upon ignition=3CaO,AsO5 + 2Ca0 AsO,. And the relative numbers are as follows Found. As 396 370 : 18*24 17.04 .. 17.02 , 396 370 : 15-50 14.47 -.. 14.70 And with regard to the quantities of lime and arsenic acid 3CaO,AsO,+ 2CaO,AsO, Calculated. Found. Lime . . 5.56 Lime . . 5-48 Arsenic Acid 9-14! Arsenic Acid 9-27 14.70 1475 Lime . . 6.44 Lime . . 6-47 Arsenic Acid 10.58 Arsenic Acid 10.44 17.02 16.91 FIELD ON THE It is not at all surprising that when ammonia is not in great excess that trisarseniate of lime should be formed as even diarseniate of ammonia produces this compound.It is however rather singular that when in combination with the diarseliiate of lime the trisarseniate does not lose arsenic acid upon ignition which it does when heatedper se.* The arseniate of lime and ammonia can be readily formed by adding ammonia and trisarseniate of ammonia to a solution of chloride of calcium. The precipitants must be in considerable excess This salt crystallises from weak solutions in large needle- shaped crystals and from more concentrated solutions it separates as a white crystalline mass. Like the baryta compound it is more soluble in water than in aqueous ammonia and soluble to a great extent in chloride of ammonium.It retains an atom of water at 212O and consists at that temperature of 2Ca0 NH,O AsO + HO. 10.00 grs. in 200OdO0 grs. water lost 0.40 grs. 10-00 grs. , , grs. weak ammonia lost 0.02 grs. 10.00 grs. , , grs. chloride of ammonium contain- ing 100 grs. dry salt lost 8.300.f This salt loses its atom of water at a temperature a little beyond 212O. Dried at 280’. Found. Calcnlsted. 18.25 on ignition gave 15-80 15.83 11.90 I> 9 10.25 10.32 13.20 >Y 9 11.48 11-45 The residues were analysed separately and found to consist of 2Ca0 AsO, as the following numbers will show :-Calculated. Found. Lime . . 5.18 5.01 Arsenic Acid 10.62 10.49 15.80 15.50 * The cold solution of this salt in chloride of ammonium evolves ammonia copiously on ebullition with formabion of diarseniate of lime which still remains dissolved in the liquid.According ta Wach diarseniate of lime when in solution of ammoniacal salts becomes converted into arseniate of lime and ammonia but this is decomposed on boiling with a re-formation of diarseniate of lime. t The trisarseniate of lime is decomposed when ignited alone (Simon) Gmelin’a Handbook vol. iv p. 301. ARSENIATES OF LIME BARYTA AND MAGNESIA. Calculated. Found. Lime . . 3.41 3.38 Arsenic Aoid 6-84 6-75 10.25 10.13 Lime . . 3-76 3.64 Arsenic Acid 7.72 7-69 11-48 11.33 Arseniate of Magnesia and Ammonia.-This salt is thrown down in great purity when arseniate of ammonia and excess of ammonia are added to a soluble salt of magnesia.In applying this salt to the estimation of arsenic Levol recom- mends its ignition and the determination of the arsenic as pyro- arseuiate of magnesia (2Mg0,AsOJ. But Rose has shown that a portion of arsenic acid is reduced at a high temperature by ammonia and volatilised so that a loss in weight due to that reaction is sustained in proportion to the necessary duration of the ignition. It is stated by the latter chemist that the weight of the double salt may be determined either by its desiccation in wacuo in which case its composition is represented by the formula 2Mg0 NH,O AsO +l2H0 or at 212' F. when it consists of- 2Mg0 NH,O AsO +HO. Like the corresponding lime salt it loses its water at a slight increase of temperature; at 180" F.it retains three atoms of water and it looses its ammonia between 500" and 600'. Its formula may be expressed at various temperatures as follows :-When dried in vaeuo 2Mg0,NH40,&0 +l2HO. From 180" to 200' 2Mg0,NH40,As0,+3H0. At 212 .. 2Mg0,NH40,As0 +HO. At 300 .. 2Mg0,NH40,As05. At 600 .. 2RXgO,AsO,. In the estimation of arsenic from this compound it is therefore very necessary to be extremely cautious in its desiccation. Speci-mens dried upon a filter placed above a sand-bath with a thermo- meter suspended at the same distance from the heated surface (the mercury never rising above 300') were found to have lQat the whole of their water in from four to five hours. 14 FIELD ON THE The following experiments were tried regarding the solubility of this double salt :-10.00 grs.digested with 2000 grs. water lost 0.28grs. 10.00 , , ammonia , 0.14 grs. JJ 10.00 9 , , NH,Cl , 1.90 grs. Ammonia precipitates the salt from its solution in chloride of ammonium. The following diagram will give in a tabular form the solu- bility of the arseniates of lime and ammonia magnesia and am- monia and arseniate of baryta in water ammonia and chloride of ammonium. 10 gw. 10 grs. 10 gra. 2MgO,NH,O,AsO, HO. 2CaO,NH,O,AsO,,HO. 3BaO,AsO,. ---I_--1 Water .... 2000 .. 0.28 2000 .. 0.40 2000 .. 1-10 Ammonia.. . 2000 .. 0-14 2000 .. 0.02 2000 .. 0.06 Chloride of Ammonium 2000 .. 1.90 2000 .. 830 2000 .. 3-85 From the foregoing experiments the relative advantages and disadvantages in the employment of the salts of the alkaline earths may be estimated and- 1.The precipitation of arsenic acid by a soluble salt of lime. This is disadvantageous when sulphuric acid is present in the liquid. Sulphate of lime would be precipitated and require long and protracted washing for its entire separation. Neither coiild the arseniates be freed from the sulphate by dilute hydrochloric acid 3s the latter is especially soluble in that menstruum. Another objection is the uncertainty of the compound precipitated which would render its analysis indispensable when the quuntity of arsenic as well as its abstraction from other bodies is desired. On the other hand its great insolubility in ammonia renders the employment of a lime-salt in certain circumstances very advan- tageous.2. The employment of a soluble baryta salt. The objection regarding the sulphuric acid cannot be urged as in the case of the lime-salt Sulphate of baryta is easily separated from its arseniate and indeed the whole of the sulphuric acid could be ARSEPU’IATES OF LIME BARYTA AND MAGNESIA. removed by chloride of barium previously to the introduction of the ammonia. When chloride of ammonium does not exist in any very great quantity in the solution the employment of baryta may be resorted to advantageoixsly. 3. By a magnesia salt. Magnesia possesses many advantages over lime and baryta which can be easily appreciated in practice.The ammonia-magnesian arseniate after standing some hours settles down in a heavy crystalline mass so hard and dense that the supernatant liquid may be frequently decanted off and the crystals drained thus rendering the subsequent washing very expeditious and easy. There is no fear of sulphuric acid being in the precipi- tate which possesses the advantage of being very definite in com-position and illsoluble in weak ammonia. From my own experi- ence I should recommend magnesia above baryta and lime if it were only for the greater facility of its management in chemical analysis. The following estimations were invariably made with a magnesian salt :-10.00 gr. arsenious acid converted into arsenic acid and preci- pitated with a magnesian salt gave 18.87 2MgO,NH,O AsO +HO.Calculation 19.19. 10.00 gr. gave 18.94. 10.00 gr. AsO, and 1gr. copper dissolved in nitric acid gave 19-14 2Mg0 NH,O AsO +HO =9.97 AsO,. 1.00gr. AsO +10.00gr. Cu gave 1-90 2MgO,NH,O AsO +HO; and when 0.19 gr. AsO,=0*076 arsenic was boiled with NO, and 100.00 of copper a crystalline deposit of the ammonia-magnesian itrseniate was observed on the sides of the flasks after standing for 24 hours. On drawing off the copper and washing the crystals with weak ammonia they mere dissolved in HC1 and a clear yellow pentasulphide of arsenic obtained on addition of a few drops of sulphide of ammonium and afterwards excess of hydrochloric acid. It has been before observed that nickel can be easily and per- fectly separated from arsenic by the introduction of a msgnesiau salt.In the following experiments with a given weight of ore (?) the arsenic was not estimated as the ore contained iron which was precipitated w ith the ammonio-magnesian arseniates. The filtrate was precipitated by sulphide of ammonium the sulphide dissolved and the nickel thrown down as oxide by potash FIELD ON THE The first experiment gave . . 6.127 oxide of nickel. second , 9 6.00 9 third , Jf 5-95 77 The Separation of Arsenic from Antimony by means of a soluble magnesian salt in the presence of ammonia is very strongly recommended by Rose; and my own experiments fully confirm the statements of that chemist. The method described in detail in his Handbook succeeds perfectly; I may state however that as the tartaric acid added to the solution of the oxidised metals for the purpose of retaining the antimony in solution is sometimes liable to occasion the separation with the arseniate of a small quantity of tartrate of magnesia and ammonia I have found it advisable to substitute sulphate of ammonia for the chloride of ammonium added previous to the ammonia.The double tartrate is very readily soluble and the double arseniate particularly in- soluble in the sulphate of ammonia. The following analyses will show the correctness of the method :-Taken. Found. Arsenious Acid 5.00 2MgO,NH,O,AsO,+ HO 9*54=4*97AsO,. Antimony . 5.00 93 Arsenious Acid 5.00 >> 9*52=4-95 AsO,. Antimony . 5.00 The antimony was not determined in the above analyses; in those below the arsenic was estimated as before sulphide of ammonium added in excess to the filtrate until the sulphide of antimony was completely re-dissolved.It was afterwards precipitated by hydro- chloric acid. The precipitate was dried at 212O weighed and a portion examined quantitatively for sulphur the weight of which was deducted and the quantity calculated from the whole precipitate. Taken. Found. Arsenious Acid . 10.00 = Arsenic 7-57 .. 7*39 T Antimony . . . -6-80 .. 7.04 -14.37 14.43 Arsenious Acid 12.40 = Arsenic 9.39 .. 9-12 -Antimony -12.40 .. 12-23 -21.79 21.35 ARSENIATES OF LIME BARYTA AND MAGNESIA. Taken. Found. Arsenious Acid 1-00 . = Arsenic 0.75 .. 0-68 Antimony .. . .= 10.00 .. 9-89 -10.75 10.57 Arsenious Acid 10.00 . = Arsenic 7.57 .. 7-42 Antimony . . . .-1.00 .. 0.98 -8.57 .. 8.40 Arsenious Acid OS1O gave a crystalline precipitate of 2MgO,NH,O,AsO +HO on the APLtim"ny 5*00 sides of the glass Arsenious Acid 5-00 filtrate gave an orange-red preci- Antimony . O*lO} pitate of sulphide of antimony. Arsenic cannot be separated from tin by means of magnesia. Ammonia produces no precipitate in the solution of the bichloride of tin when tartaric acid is present but a precipitate is produced by the introduction of magnesian salts which appears to contain both tin and magnesia but which so far as I know has not been examined. Hopes may be entertained that antimony may be separated from tin by taking advantage of this fact.The subject is now under consideration and promises satisfac. tory results though rat her difficult and laborious.

ISSN:1743-6893    

DOI:10.1039/QJ8591100006

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

ARSENIATES OF LIME BARYTA AND MAGNESIA. 111.-On the existence of a Second Grystallizabb muorescent Substance (Paviin) in the Bark of the Horse-Chestnut. BY G. G. STOKES, MA. SEC.R. S. &c. ON examining a good while ago infusions of the barks of various species of Bsculus and the closely allied genus Pavia I found that the remarkably- strong fluorescence shown by the horse- chestnut ran through the whole family. The tint of the fluores-cent light was however different in different cases being as a general rule blue throughout the genus Bsculus and a blue-green throughout Pavia. This alone rendered it evident either that there were at least two fluorescent substances present one in one bark and another in another or which appeared more probable that VOL.XJ. C STOKES ON A SECOND CRYSTALLIZABLE there were two (or possibly more) fluorescent substances present in different proportions in different barks. On examining under a deep violet glass a freshly cut section of a young shoot of at least two years’ growth of these various trees the sap which oozed out from different parts of the bark or pith was found to emit a differently coloured fluorescent light. Hence even the same bark must have contained more than one fluorescent substance; and as the existence of two would account for the fluorescent tints of the whole family a family so closely allied botanically the second of the suppositions mentioned above appeared by far the more probable. I happened to put some small pieces of horse-chestnnt bark with a little ether into a bottle which was laid aside imperfectly corked.On examining the bottle after some time the ether was found to have evaporated and had left behind a substance crystal- lized in delicate radiating crystals. This substance which I will call paviin when dissolved in water yields like aesculin a highly fluorescent solution and the fluorescence is in both cases destroyed (comparatively speaking) by acids and restored by alkalies. The tint however of the fluorescent light is decidedly different from that given by pure mculin for a specimen of which I am indebted to the kindness of the Prince of Salm-Horstmrtr being a blue-green in place of a sky-blue. The fluorescent tint of an infusion of horse-chestnut bark is intermediate between the two but much nearer to xwulin than to paviin.In all probability the fluorescence of the infusions of barks from the closely allied genera Bsculus and Pavia is due to mculin and paviin present in different proportions xsculin predominating generally in the genus Bsculus and paviin in Pavia. Bsculin and paviin are extremely similar in their properties so far as they have yet been observed. They are most easily distin- guished by the different colour of the fluorescent light of their solutions a character which is especially trustworthy as it does not iequire for its observation that the solutions should be pure. Paviin as appears from the way in which it was first obtained must be much more soluble than aesculin in ether.Bsculin is indeed described as insoluble in ether but it is siifficiently soluble to render the ether fluorescent Paviin like aesculin is withdrawn from its ethereal solution by agitation with water. Though of feeble affinities it is rather more &posed than zsculin to combine with oxide of lead. If a decoction of horse-chestnut bark be SUBSTANCE IN THE HORSE-CHESTNUT. purified by adding a sufficient quantity of a salt of peroxide of iron or of alumina precipitating by ammonia and filtering and the ammoniacal filtrate be partially precipitated by very dilute acetate of lead the whole redissolved by acetic acid reprecipitated by ammonia and filtered the fluorescent tint of the filtrate will be found to be a deeper blue than that of the original solution; while if the fluorescent substances combined with oxide of lead (the compound itself is not fluorescent) be again obtained in alkaline solution the tint as compared with the original will be found to verge towards green.The required solution is most easily obtained from the lead-compounds by means of an alkaline bicarbonate which plays the double part of an acid and an alkali yielding carbonic acid to the oxide of lead and ensuring the alkalinity of the filtrate from carbonate of lead. It is very easy in this way by repeating the process if necessary on the filtrate from the first precipitate to obtain a solution which will serve as a standard for the fluoreecent tint of pure aesculin. A solution serving nearly enough as a standard of comparison in this respect for pure paviin may be had by making a decoction of a little ash bark adding a considerable quantity of a salt of alumina precipitating by ammonia and filtering.By partial precipitation in the manner explained it is very easy to prove a mixture of zsculin and paviin to be a mixture even when operating on extremely small quantities. It must be carefully borne in mind that the characteristic fluor- escent tint of a solution is that of the fluorescent light coming from the solution directly to the eye. Even should a solution of the pure substance be nearly colourless by transmitted light though strong enough to develope the fluorescence to perfection if the solution be impure it is liable to be coloured most com- monly yellow of some kind which would make a blue seen through it appear green.To depend upon the fluorescent tint as seen through and modified by a coloured solution would be like depending on the analysis not of the substance to be investigated but of a mixture containing it. Yet in solutions obtained from the horse-chestnut and in similar cases the true fluorescent tint can be observed very well in spite of considerable colour in the solution. The best method of observing the true fluorescent tint is to dilute the fluid greatly and to pass into it a beam of sunlight condensed by a lens fixed in a board in such a manner that as c2 STOKES ON A SECOND CRYSTALLIZABLE small a thickness of the fluid as may be shall intervene between the fluorescent beam and the eye.If a stratum of this thickness of the dilute eolution be sensibly colourless the tint of the fluor-escent light will not be sensibly modified by subsequent absorp- tion. This however requires sunlight which is not always to be had. Another excellent method requiring only daylight and capable of practically superseding the former in the examination of horse-chestnut bark is the following in using which it is best that the solutions should he pretty strong or at least not extremely dilute. A glass vessel with water is placed at a window the vessel being blackened internally at the bottom by sinking a piece of black cloth or velvet in the water or otherwise. The solutions to be compared as to their fluorescent tint are placed in two test tubes which are held nearly vertically in the water their tops slightly inclining from the window and the observer regards the fluores- cent light from above looking outside the test tubes.Since by far the greater part of the fluorescent light comes from a very thin stratum of fluid next the surface by which the light enters the fluorescent rays have mostly to traverse only a very small thickness of the coloured fluid before reaching the eye; the water permits the escape of those fluorescent rays which would otherwise be internally reflected at the external surface of the test tubes; and the intensity of the light of which the tint is to be observed is increased by foreshortening. The observer would do well to practice with a fluorescent fluid purposely made yellow by intro- ducing some non-fluorescent indifferent substance ;thus a portion of the standard solution of esculin mentioned above may be ren- dered yellow by ferrid-cyanide of potassium.The more com-pletely the fluorescent tints of the yellow and the nearly colourless solution agree the more nearly perfect is the method of observa-tion. If ferro-cyanide of potassium be used in the experiment suggested instead of ferridcyanide the most marked effect is a diminution in the intensity of the fluorescent light the cause of which is that the absorption by this salt takes places more upon the active or fluorogenic than upon the fluorescent rays. Since sub- stauces of a similar eharacter may be present in an impure solution the observer must not always infer poverty with regard to fluor- escent substances from a want of brilliancy in the fluorescent light.The existence of paviin may perhaps account for the discrepan- cies between the analyses of ssculin given by different chemists. SUBSTANCE IN THE HOltSE-CHESTNUT. I should mention however that I have met with three specimens of zesculin and they all appeared to be free from paviin. The reason why asculin was obtained pure from a decoction containing paviin also is probably that the former greatly preponderates over the latter in the bark of the horse-chestnut. A decoction of this bark yielded to me a copious crop of crystals of mculin while the paviin together with a quantity of mculin still apparently in excess remained in the mother liquor.I map perhaps on some future occasion communicate to the Society the metliod employed when I have leisure to examine it further; I will merely state for the present that it enabled me to obtain crystallized zesculin in a few hours without employing any other solvent than water. In the method commonly employed the first crystallization of aesculin is described as requiring some fourteen days. On account of the small quantity apparently of paviin as com- pared with mculin present in the bark of the horse-chestnut a chemist who wished to obtain the substance for analysis would probably do well to examine a bark from the genuspavia if such could be procured. The richness of the bark in paviin as compared with mculin may be judged of by boiling a small portion with water in a test tube; those barks in which the substance presumed to be paviin abounds yield a decoction having almost exactly the same fluorescent tint as that of a decoction of ash bark.A crystallizable substance giving a highly fluorescent solution has been discovered in the bark of the ash by the Prince of Salm-Horstmar,* who Elas favoured me with a specimen. This sub-stance which has been named fraxin by its discoverer is so similar in its optical characters to paviin that the two can hardly if at all be distinguished thereby; but as fraxin is stated to be insoluble in ether it can hardly be identical with paviin which was left in a crystallized state by that solvent. I find however that fraxin is sufficiently soluble irr ether to render the fluid fluor-escent so that after all it is only a question of degree which cannot be satisfactorily settled till paviin shall have been prepared in greater quantity. *Poggendorffs Annalen vol. 100 (1857) p. 607.

ISSN:1743-6893    

DOI:10.1039/QJ8591100017

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

22 IV.-On the Action of Bromine on Acetic Acid. BY VC'. H. PERKIN, F.C.S. AND B. F. DUPPA ESQ. SINCEthe publication of the notice which appeared in the "Philosophical Magazine" last September we have studied some of the reactions of bromacetic acid on various substances and have also succeeded in obtaining bibromacetic acid. We shall first describe the method pursued in making these interesting substances. Bronzacetic Acid. The best method of preparing this substance is to take a mix- ture of crystallizable acetic acid and bromine in the proportion of one equivalent of bromine to one of acid the object of the excess of acetic acid being to absorb the hydrobromic acid gas so as to relieve the tube of pressure and introduce it into a strong sealed tube which is then placed in an oil bath and heated up to 150"C.As soon as this temperature has been reached the bath may be allowed to cool down gradually; the cooling may occupy two hours or more. The mixture is then generally nearly colourless or of a light amber-brown. The decolorization takes place very suddenly at ahout 146"C. at which moment the tubes are apt to burst though the bath may have been as high as 155OC. The tube when quite cold is opened from which torrents of hydrobromic acid gas issue ; the contents are then transferred to a retort and a receiver being attached together with proper apparatus for the condensation of the hpdrobromic acid liberated heat is applied and the tempera- ture raised until it reaches 200" C.* The retort is then left to cool when after a time the whole of the liquid contents become solid and beautifully crystalline.This is a mixture of hy drobromic bromacetic and bibromacetic acids. These mixed acids are then heated to 130' C. and carbonic acid passed until the reaction of hydrobromic acid with nitrate of silver is no longer evident. Carbonate of lead in excess is then added together with about ten times as much water in bulk as there is acid ;the whole heated to 100' C. and allowed to stand for some hours; the liquid filtered off from the crystalline deposit which has formed; the As a quantity of bromacetic acid is carried over loiig before 200' C. is reached it is as well to re-distil the distillate. As an additional quantity of solid acid is thus procured the liquid may again be used with bromine for the productiou of more acid.ON THE ACTION OF BROMINE ON ACETIC ACID. crystals washed with a little cold water and diffused in water ;and sulphuretted hydrogen passed to saturation. The liquid filtered off and concentrated yields the crystalline acid in a state of purity. The object of the last process is to separate the bromacetic acid from the bibromacetic acid the lead salt of the latter being much more soluble than that of the former. The acid thus obtained crystallizes in rhombohedra; it is exceed- ingly deliquescent and very soluble in water or alcohol. It fuses below 100"C. and boils at 208' C. When distilled with acetate of potassium it gives off acetic acid; when heated witli metallic zinc it yields acetate and bromide of zinc.It undergoes a singular change when exposed to a high tempera- ture in a sealed tube carbonic oxide bibromacetic acid and appa- rently a little hydride of methyl being formed; it is possible that the following reaction may take place Bromacetic acid. Bibromacetic acid. It attacks the epidermis powerfully raising a blister like that produced by a burn; the effect when the acid is diluted takes place after eight or ten hours. Bromacetic acid forms crystallizable salts with most of the bases many of which decompose rapidly; few of these have been examined quantitatively . Bromacetate of Ammonium is a nearly uncrystallizable salt very soluble in water ;when heated it decomposes yielding bromide of ammonium.Bromacetate of Potassium. This salt is obtained by neutralizing a solution of carbonate or hydrate of potassium with bromacetic acid and evaporating the solution in a water bath. It is a crys- talline salt very soluble in water and alcohol. Bromacetate of Sodium is a very soluble salt insolublc or nearly so in alcohol. Bromacetate of Barium crystallizes with difficulty in small stars and contains water of crystallization; it is tolerably soluble in alcohol. Bromacetate of Calcium is a very difficultly crystallizable salt and very soluble in water. Bromacetate of Copper is a green crystalline salt very soluble in PERKIN AND DUPPA ON THE water. A solution of it appears to decompose when boiled as the colour becomes paler.The solution after stailding for some days deposits needle-shaped crystals and small malachite-green tufts of great beauty. They appear to contain a large quantity of water of crystallization. Bromacetate of Lead.-This salt is obtained either by neutra- lizing bromacetic acid with oxide of lead and recrystallizing the product in water or by adding a solution of bromacetic acid to a solution of acetate of lead washing the resulting crystalline pre- cipitate with cold water and then recrystallizing from water. A specimen dried at 100' C. when burnt with chromate of lead gave the following numbers ,9880 of Brornacetate of Lead gave *3717of Carbonic Acid and 00830of Water. A determination of lead and bromine gave the following numbers -674 of Bromacetate of Lead gave ,3106of Oxide of Lead and b5244of Bromide of Silver.These numbers lead to the following percentage composition Carbon .. .. .. 10.25 Hydrogen. . .. .. 0-92 Bromine .. .. .. 33-10 Lead .. .. .. 42.774 The formula requires the following numbers Theory. Exp. / h \ 4 equiv. of Carbon = 24.00 9.930 20.25 2 equiv. of Hydrogen= 2-00 0-820 '92 1 equiv. of Bromine = 79.97' 33.117 33.10 1 equiv. of Lead =103-57 42-878 42.774 4 equiv. of Oxygen = 32-00 13-255 1__1 241.54 100.000 ACTION OF BROMINE ON ACETIC' ACID. Bromacetate of lead crystallizes in needles is difficultly soluble in cold but moderately so in hot water. Bromacetate of Silver is obtained by treating bromacetic acid with carbonate of silver or by adding a solution of brornacetic acid to a solution of nitrate of silver.In the latter case it is thrown down as a beautiful crystalline precipitate which is washed with cold water and dried over sulphuric acid in vacuo. A determina-tion of the silver gave the subjoined number ; 06500of Bromacetate of Silver gave -4935of Bromide of Silver or 43.617 per cent. of Silver. The formula requires 48.9 per cent. of silver. This salt is very unstable decoimposing by ebullition bromide of silver and an acid which we shall refer to hereafter being formed. The dry salt if heated to about 90°C. decomposes with a sort of an explosion. It is rapidly acted upon by light when moist. Bromacetate of Methyl.-This substance is obtained by heating a mixture of hydrate of methyl and bromacetic acid in a sealed tube for an hour to a temperature of looo C.washing the product with water drying over chloride of calcium and rectifying. Bromacetate of methyl is a clear colourless mobile liquid having an aromatic odour highly irritating both to the nose and the eyes. It is heavier than water; it boils at about 144O C. decomposing gradually every time it is distilled. Ammonia acts on it very readily. Bromacetate of Ethyl is obtained in the same way as the pre- ceding substituting hydrate of ethyl for that of methyl. It is a clear colourless liquid heavier than water and highly irritating to the eyes and nose. It boils at 159' C. A combustion with chromate of lead yielded the following numbers 0.3821of substance gave 0.3922 of Carbonic Acid and 0.1215 of Water.PGREIN AND DUPPA ON THE A determination of bromine gave the following numbers 0.4942 substance gave 0.5110 of Bromide of Silver. These numbers give the following percentage composition Carbon .. .. .. 27.976 Hydrogen.. .. .. 3.533 Bromine .. .. .. 47.53 The formula C,H,BrO requires the following numbers Theory. Exp. -8 equiv. of Carbon 48.00 28.70 27'976 7 equiv. of Hydrogen 7.00 4.18 3-533 I equiv. of Bromine 79-97 47.70 47.530 4 equiv. of Oxygen 32.00 19-42 166.97 100*00 This substance decomposes partially every time it is distilled with evolution of hydrobromic acid. It is rapidly acted on by ammonia.Brornacetate of Amyl is obtained by heating hydrate of amyl with an excess of bromacetic acid washing the product with water and drying over chloride of calcium. It is an oily liquid having a pleasant odour when cold but if heated acts upon the eyes and nose like the preceding. It boils at 207°C. and decomposes partially every time it is distilled. Ammonia acts but slowly upon this substance in the cold. Two combustions of this substance gave the following results I. grm. -5091 of Bromacetate of Amy1 gave *7658of Carbonic Acid and 02916of Water. 11. -4829of Bromacetate of Amy1 gave -7071 of Carbonic Acid and *2675 of Water. ACTION OF BROMXNE ON ACETIC ACID. Percentage composition. I. Ii. Carbon .. . . 410.08 39.97 Hydrogen . . . . 6.41 6-15 which agrees with the formula as may be seen by the following comparison of the theoretical and experimental numbers 14 equiv. of Carbon 84.00 40.19 40.02 13 , Hydrogen 13-00 6.22 6.28 1 , Bromine 79-97 38.22 -4 , Oxygen 32.00 15-37 -208.97 100*00 A curious relationship exists between the boiling points of the acetates and the bromacetates of methyl ethyl and amyl. Although constant boiling points have not been obtained with the bromacetic ethers yet if the highest point at which the largest proportion comes over be taken it will be found that the bro-macetates boil at a temperature from about 82' to 86" C. higher than the corresponding acetates. Thus-Boiling Boiling point point. Di5.Bromacetate of Methyl 144" Acetate of Methyl 58" 86" 9 Ethyl 159" , Ethyl 74" 85" 1 Amyl 207" , Amyl 125" 82" A similar difference also exists between the boiling points of bromacetic and acetic acids. Boiling point of Bromacetic Acid = 208" ,> , Acetic Acid = 120" -88 diff. Could these substances be distilled without decomposition and a constant boiling point obtained it is very probable that the numbers would agree much more closely. PERKIN AND DUPPA ON THE Bibromacetic Acid. This acid is formed when a mixture of bromine and acetic acid is heated in presence of light; also in small quantities when bromacetic acid is heated. It is difficultto obtain in large quan- tities. We are at present endeavouring to find a process by means of which it may be produced with certainty in any quantity.Bibromacetic acid is a liquid boiling at about 240"C. ; it is decomposed partially every time it is distilled evolving hydro- bromic acid. It does not solidify at 15"C. It is possible that by the continued action of heat it might be transformed into tribro- macetic acid. Its specific gravity is very great. Bromacetic acid forms salts with most bases; they are in general uncrystallizable. Bibromacetate of Burium is deliquescent drying up to a gum- like sticky mass. Bibromacetate of Lead is uncrystallizable drying up to a highly refractive transparent substance attracting moisture and becoming opaque. It is very soluble in water. Bibromacetate of SiZwer is obtained by adding nitrate of silver to a solution of bibromacetic acid when it falls down as acrystalline precipitate.It is decomposed by ebullition with water into bro-mide of silver and a soluble acid. Two silver and one bromine determinations gave the following numbers I. *922of Bibromacetate of Silver gave 04196of Chloride of Silver. 114 06446of Bibromacetate of Silver wheu heated with carbonate of soda &c. gave $2154 of Metallic Silver '7160 of Bromide of Silver. Percentage composition. I. IT' Silver . . . . 33.0 33.41 Bromine . . .. -49-26 These numbers agree with the formula ACTION OF BROMINE ON ACETIC ACID. as may be seen by the following table : -Theory. Exp. 7 4 equiv. Carbon 24.00 7.364 7 2 , Hydrogen 2.00 0,613 1 , Silver 107.97 33.128 33.2 2 , Bromine 159.94 49.074 49-26 4 >t oxygen 32-00 9.821 -325-91 100.000 Bibromacetate of Ethyl is obtained by heating hydrate of ethyl with bibromacetic acid in a sealed tube at a temperature of 100"C.washing the product with water and drying over chloride of calcium. It is a colourless liquid heavier than water. It acts on the eyes and nose like the bromacetate of ethyl. It is possible that if a salt of bibromacetic acid were treated with sodium or metallic zinc an acid might be obtained standing to acetic acid in the same relation as acrylic acid stands to pro-pionic acid. M,C,(HBr,)O + 2Na = M C4H0 -t 2NaBr. We have lately studied the action of ammonia on brornacetic acid and have obtained some exceedingly interesting results.We find that when bromacetic acid is heated with ammonia there is formed a large quastity of bromide of ammonium and a beautiful white sweet tasting substance which we think without hesitation we may say is Glycocol. We have made a combustion of this substance gave the following numbers *3256of Substance gave *3837of Carbonic Acid and *1920of Water. Percentage composition. Carbon . . .. . . 3.21 Hydrogen . . .. *. 6-53 ON THE ACTION OF BROMXNE ON ACETIC ACID. The formula C,H5N0 requiring Carbon . .. .. 32.0 Hydrogen .. .. .* 6.6 There cannot therefore be any doubt as to the composition of this product being identical to that of Glycocol ; nevertheless we hope soon to give some confirmatory numbers.We also find that on boiling the bromacetate of silver in water we obtain a powerful syrupy acid and which has all the properties of glycollic acid. The formation of glycol and glycollic acid from bromacetic acid may eaaily be understood by the following equations C,(H,Br)O + 2NH = C4H,N0 + NH4Br GlyColl. Ag C4(H3Br)O4 + H,O = C4H406 + AgBr -Glycollic acid. We hope when we have completed our investigations on the formation of glycol and glycollic acid to give an account of the action of ammonia and of hydrate of silver on bromacetic acid and also of the action of zinc-methyl and zinc-ethyl on these new bromo-acids.

ISSN:1743-6893    

DOI:10.1039/QJ8591100022

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

ON THE ACTION OF BROMXNE ON ACETIC ACID. V.-On the Use of Gas as Fuel in Orgaazic Analysis. BY A. W. HOFMANN. SOMEyears ago* I described a gas-furnace which I then used for combustions. The apparatus in question furnished very valuable results but has many imperfections which I did not leave unnoticed at that time. The wire-gauze over which the air-flame of the gas is lighted is rapidly destroyed and must be often renewed ; frequently the wire-gauze becomes perforated during a combustion the flame then descends and the heat can no longer be regulated. The greatest inconvenience however of * Journ. of the Chem. SOC.,vol. vi p. 209. ON THE USE OF GAS AS FUEL IN ORGANIC ANALYSIS. 31 this furnace arises from the fact that the temperature which it yields is barely sufficient for a combustion in the ordinary way; 60 that even suhstances which when mixed with oxide of copper readily burn in a charcoal fire involve the necessity of completing their combustion by a current of oxygen.The simplicity of Liebig’s original method which has contributed so much to the rapid progress of organic chemistry is thus more or less com-plicated. The combustion-furnace described by me has been repeatedly modified. The alterations however which have been suggested generally refer to special parts of the apparatus the mode of admitting the gas has been changed instead of the piston which I had adopted a system of valves or stop-cocks has heen found by others more convenient &c. In most cases however the original method of burning a mixture of gas and air over a wire-gauze has been retained.Since I was by no means satisfied with my apparatus I have during the last two or three gears tried nearly all the alterations which have been proposed by others without however obtaining a furnace possessing all the qualities which I could have desired. I therefore tried new constructions and ultimately entirely gave up the old method. After much time and FIQ. 1. labour which I have devoted to this subject I have at last arrived at an apparatus which has not only satisfied myself personally but which has been rapidly adopted in many of the London laboratories. In reply to several inquiries which have been addressed to me on this subject I give in the following pages a short description of the new furnace.Several years ago a peculiar clay burner was introduced under the name of atrnopyre which I think has scarcely received from che- mists the attention which it deserves. This burner is a hollow cylinder of burnt clay closed at the top open at the bottom and with nume-rous perforations through the sides. Those which I use and which are represented in fig. 1 are 3inches high of Q inch exterior and +inch interior diameter. The perforations are of about 32 HOFMANN ON THE USE OF the thickness of st pin are made in rows; their number varies those which I employ have ten rows each of fifteen holes. From such a clay cylinder loosely fixed upon an ordinary bat’s-wing burner the stop-cock of which has been appropriately adjusted the gas burns with a perfectly blue flame which enve- lopes the cylinder and renders it in a short time incandescent.These clay burners being readily obtainable and very indestruct-able I have tried to construct a complete combustion-furnace for organic analysis by appropriately grouping together a number of them. The result of the experiment has surpassed my most sanguine expectations. The disposition of the apparatus being obvious from the accom . panying wood-cuts a few explanatory remarks may be sufficient. FIG2. Into a brass tube a of from 3 feet to 3 feet 8 inches length and 1inch diameter (shown in section in fig. 2) which communicates at both ends with the gas-main of the laboratory there are screwed from twenty-four to thirty-four tubes b.These tubes Q inch tbick and 7 inches high are provided with stop- cooks and carry brackets cc of 46 inches length and 8 inch diameter for ac Horizontal gas-pipe. the reception of five ordinary bat’s-wing b Vertical gas-pipe pro-burners (each consuming from 3 to 4 vided vith stopcock. cc Bracket for burners. cubic feet of gas per hour for a full lumin- dddd High clay burners. ous effect) upon which a corresponding e Low clay burner. f Oombustion-tube. number of clay-burners is fixed. These gg Wrought iron frame. clay burners dddd have the dimensions hh Cast iron supports. ii Cast iron foot-plate. before stated with the exception of the && Side plates of fire-clay.middle one which is only 1%inches U Cover plates of fire-clay. high and has only seventy or eighty perforations. It serves as support for the oombustion-tube f which is thus bedded in a channel of heated fire-clay. The system of brackets lying side by side acquires sufficient stability by a strong iron frame 99 which rests upon two firm sup-ports hh of cast iron fastened down by screws upon the foot- plate ii likewise of cast iron. The iron frame gy has moreover a groove for the reception of moveable side plates of fire-clay kk. They are of the same height as the high burners over which they project but about; 8 inch in consequence of their resting GAS AS FUEL IN ORG-4NIC ANALYSIS. upon the frame g; lastly ZZ are covering plates likewise of fire-clay which are supported by the side plates kk.The whole disposition of this apparatus will be best understood by a glance at the perspective view given in fig. 3.* FIG. 3. In the front part contiguous to the potash-apparatus the side plates and the covering plates are omitted in order to show the disposition of the burners. During the combustion however all the burners are inclosed as exhibited in the posterior part of the apparatus. It deserves to be noticed that the efficiency of the furnace essentially depends upon the correct disposition of the gas-jets. The most appropriate space between the several burners according to numerous experiments made for the purpose is about + inch. It is very important for the attainment of a perfectly uniform temperatime that the several brackets bearing the burners should be equidistant.Their position is therefore specially secured by every bracket being fixed in an aperture formed in the iron frame gg (fig. 2). The use of the furnace scarcely requires any special remark. According to the length of the combustion-tube from 8 to 10 stop-cocks (under all circumstances the largest possible number) are opened at once at the commencement of a combustion. If care has been taken to regulate the amount of gas either by the stop-cocks in the horizontal gas-pipe or by those in the separate supply-tubes the lighted portion of the furnace in 10or 12minutes will be in a state of perfect incandescence comparable only to the igiiited mass of charcoal in an ordinary combustion-furnace * The engraving is taken from the 7th edition of Fomnes’ Manual of Chemistry, London 1858 John Churchill VOL.XI. 1) HOFMANN ON THE USE OF After this it is only necessary to open the remainder of the stop- cocks in appropriate succession to insure a slow and regularly progressing combustion. The time required for the completion of an analysis varies from 40 minutes to an hour. Only in extra-ordinary cases a longer time may be required. The heat obtained by this furnace is extremely uniform and since it is conveyed to the combustion-tube chiefly by radiatioii from the incandescent mass of surrounding clay every part of the tube is equally heated. It is in this respect especially that the new apparatus differs from all former contrivances of this kind.The temperature which it is capable of yielding is entirely at the command of the operator. When strained to its full power it gives a heat equal to that of the strongest charcoal combustion-furnace at which even the most refractory Bohemian tubes readily fuse; by appropriately adjusting the stop-cocks however it is possible to maintain the furnace at any desired temperature especially since it is only necessary to look into the channel when with a little practice a correct idea of the temperature is rapidly obtained from the colour of the glowing cylinders. It deserves however to be noticed that the apparatus furnishes rather more than less heat tliari is generally required ; it is preferable therefore under all circum- stances to protect the combustion-tube by a metallic shield for this purpose ordinary brass-wire gauze may be conveniently ern- ployed ;which is more easily manipulated and may be used longer than the thin copper or brass plate generally employed.From what has been stated it is obvious that the furnace may be used in many operations in which charcoal has hitherto been con- sidered almost indispensable. During the time I have had it in use it has served in all kinds of analyses from the combustion of ether to the carbon-determination in cast iron. It is scarcely requisite to be mentioned that the combustion may be made with or without oxygen as the case may necessitate. In all other tube-operations in passing gases or vapours through red-hot tubes (preparation of propylene gas) in reducing copper-turnings &c.the apparatus may be used with equal advantage ; for the latter operation vhich has to be so frequently repeated it is found convenient to re-arrange the burners in such a manner as to obtain by the introduction of a second row of small burners in the place of large burners two gutters or channels in wliicli two glass tubes connected by means of caoutchouc with the same hydrogen-apparatus may be heated at Qnce In like mmner two combustion-tubes similarly filled with GAS AS FUEL IN ORGANIC ANALYSIS. 35 et similar mixture have been actually heated simultaneously. If short combustion-tubes are to be heated such as are used in iitrogen-determinations an additional advantage may be obtained by simultaneously operating on both sides of the apparatus.One of the great advantages of this furnace is its durability; one that I have had in almost daily use during ten months is as good as new at the present moment. The clay burners as I have stated already are very indestructible but even in case of a burner splitting it may be rapidly removed and replaced even during an analysis. The clay plates also when well burnt are very durable and often serve for months even after they are split. At first I was somewhat afraid the minute holes in the clay burners might become stopped up by carbon; but the mixture of gas and atmospheric air is so perfect and the diffusion of the com-bustion is so great (in the apparatus which I use the gas issuing from between 24,003 aid 25,000 apertures) that neitl-rer upon tlic burners nor in the perforations is the slightest trace of carbon deposited.It remains now only to mention a few experiments which were made in order to determine the quantity of gas consumed by the apparatus. These experiments were performed in the laboratory of my friend Mr. J. J. Evans of the Chartered Gas Company who kindly placed his instruments at my disposal. It was found that a combustion lasting one hour and requiring the whole length of the furnace (34rows of burners) consumes from 80 to 90 cubic feet; the maximum ever observed being 100 cubic feet. For a car-bon-determination with 24 rows of burners which generally lasts about 40 minutes from 50 to 60 cubic feet are required; for it nitrogen-determination from 25 to 30 cubic feet.Perfectly similar results have been observed by Dr. Watson. From these data it is obvious that this apparatus is Fig. 4. a very economical one especially in loca- lities where gas is cheap and charcoal dear. In laboratories therefore where many combustions are made the saving of fuel will readily cover the original outlay for the furnace. The cost of the apparatus and the con-sumption of gas can be still further dimi- nished by reducing the number of the rows 1. -L of burners from 5 to 3. Fig. 4 shows the section of such a furnace which has furnished me good results. D2 DR. GLADSTONE ON THE Such a furnace of course does not yield the same degree of temperature as the larger one it also requires a few minutes more to produce the full effect; but in few cases will a higher temperature be necessary for combustions.Such a smaller appa- ratus is also very useful in lectizres when a fuyther simplification may be effected by a diminution of the number of the stop- cocks. In conclusion I offer my best thanks to my friends Dr. Watson and Dr. H. Miiller whose interest in the apparatus has greatly facilitated its construction. My thanks are also due to MY.R. H. Hess who was entrusted with the manufacture of the furnace and to whose perseverance during many alterations I am indebted for an apparatus which I should not like to miss any more in my researches.

ISSN:1743-6893    

DOI:10.1039/QJ8591100030

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

DR. GLADSTONE ON THE V1.-On the Chemical Action of Water on Soluble Salts. BY DR. J. H. GLADSTONE, F.R.S. INpursuing my researches on chemical affinity among substances in solution it seemed desirable to ascertain if possible what specific chemical action water exerted on a salt. Unfortunately my expe-riments in this direction have not led to any such conclusive result as I had hoped; yet during the course of the inquiry many obser- vations were made which I believe to be new and some of which I think are not unworthy the notice of chemists. In order to bring these observations clearly before the minds of others it may be well to associate them with the leading trains of thought that presented themselves to my own mind during the in-vestigation ; and as in a difficult discussion it is very necessary to examine the simpler before attempting the more complex pheno- mena it will be wise to confine the attention first to simple salts and indeed to begin by trying to ascertain what is the action ol water on such a salt before it dissolves it.Anhydrous salts will frequently absorb water a.nd still remain solid bodies either amorphous or crystallized. In such a case the water combined in the solid form is always in atomic relation with the salt itself. The language of chemists implies the general belief CHEMICAL ACTION OF WATER ON SOLUBLE SALTS. that a certain number of equivalents of water are then simply added to the original salt; yet great heat is often evolved and a change of colour frequently ensues.* I.know of no reason to think that the water in such a case has been decomposed by the salt (whose composition may be expressed by the general formula MR) and that the resulting solid contains any such compound as MO,HR though should any one choose to advance such a view he would not be wholly without arguments to support it. These ‘c hydrated” salts are usually but not always soluble in water. When solution does take place those difficulties as to their rational composition of which we have already seen the commence- ment increase ; for there is now scope for more varied chemical actions and consequently for a wider range of speculation. The water may act merely as a solvent ;or it may unite without decom- position with the dissolved salt becoming an integral part of it ;or it may exert an action similar to what usually takes place when two binary compounds are united under such circumstances that all the resulting bodies are free to act and react namely that recipro- cal decomposition ensues each electro-positive element combining with each electro-negative one in certain proportions ; or the ulti- mate result may be due to two or more of these modes of action in conjunction.Usually when a ‘(hydrated” salt is dissolved in a minimum of water nothing is observable beyond a change in its state of aggre-gation and the new physical properties and the absorption of heat resulting from that. No change of colour as far as I can find ever ensues. A change in fluorescence may occur.? There is no atomic relation between the quantity of salt dissolved and the quantity of water indeed the ratio varies with the degree of tem-perature.Here we seem to have the simplest case of solution such as we necessarily conceive when a salt dissolves in ether or a fat in an essential oil. When an anhydrous salt which will not combine with water to produce a solid compound dissolves in that liquid the same pheno- mena usually present themselves except that a change in colour * For a cage in point and some remarks on it gee my paper “On the Colour of Chloride of Copper in Different States of Hydration.” Quart. Journ. Chem. Soc. viii 211. .t. As in the case of crystallized salts of uranium which are much more 0uorescent than their saturated solutions.See the paper of Prof. Stokes Phil. Trans. 1852 517 This observation as every other quoted or reasoned on in this communication has been verified by myself DB GLADSTONE ON THE may occur; as in the case of red prussiate of potash which gives a green saturated solution. Sometimes however an evident decomposition ensues the hydrogen and oxygen of the water combining each with one of the elements of the other binary compound and the products of this action remaining uncombined This is commoii among the com- pounds of the non-metallic bodies-as for instance the chlorides of phosphorus,-and is not unknown among what are more properly called salts for instance chloride or nitrate of bismuth or sulphate phosphate or citrate of ammonia.In such cases the decomposi- tion makes itself manifest by the separation of the one resulting substance from the other. The bismuth salt treated with water forms an insoluble subsalt; the compound of ammonia with a polybasic acid gives off some of the volatile alkali when its solution is heated while the liquid itself becomes acid. It is certain how-ever that in the vast majority of cases of solutions of salts no such interchange takes place with the production of a new oxygen aiid a new hydrogen compound uncombined; if chloride of copper be dissolved no oxide of copper or subsalt is precipitated and no hydrochloric acid can be boiled off. Yet it has been contended that a haloid salt in dissolving ceases to be of the constitution MR and becomes MQ HE; only that the two new pi*oducts instead of separating fmm one compound body.When this theory was started there was supposcd to be a wide difference in the essential constitution of haloid and other salts ;our views have now changed and there seems to me now no logical grounds on which if we consider a haloid salt in solution to be MO,HR we can stop short and refuse to consider this as the general expression of any salt in solution I was unacquainted with any argument of weight in support of this hypothesis ; yet on the other hand it had never been actually disproved. Analogy too led me toviem it with some favour for it seemed reasonable to suppose that water might act like hydro- chloric acid or a similar hydrogen compound and that possibly an aqueous solution of a salt might resemble a solution of ferric phosphate in hydrochloric acid which contains portions of both the original salt and the hydracid mixed with ferric chloride and phosphoric acid.* The action of HQ 011 AIR wonJd by aualogy * See my paper in the Quart.Journ. Cbem. SOC. ix 152. Of course water was present in the reaction alluded to there but I have repeated it in absolute alcohol with a similar result. CHEMICAL ACTION OF WATER ON SoLUnLE SALTS 39 result in a reciprocal decomposition MO and HR being formed- either separate or in combination-while portions of the original I30 and MR coexisted in the same solution. But how was this to be decided? By all analogy it might be anticipated that by increasing the amount of HO more MR would be decomposed just as the addition of more hydrochloric acid to a solution of ferric phosphate in that acid produces more ferric chlo- ride and heightens the colour.The action of water when added to a saturated solution of a salt becomes therefore a matter of peculiar interest. That such an addition of water produces a decomposition issome-times evident from the separation of a precipitate-and that in several different mays. Thus :-Pentachloride of antimony as is well known though soluble in a small amount of water is decomposed by a larger quantity giving rise to hydrochloric acid and an oxychloride of the com- position SbClO, according to Yeligot. A strong solution of ferric sulphate if diluted with water deposits a subsalt 3Fe,O,,SO + ‘IHO.* The intensely blue solution of crystallized ammoniacal nitrate or sulpliate of copper in a little water is perfectly clear but on dilution it becomes turbid from the separation of a subsalt the quadrobasic sulphate mhile free ammonia is perceived in the solution Nitrate of bismuth if slightly acid dissolves in a little water but forms a white precipitate of varying composition when this is poured into a larger quantity.In all these cases the amount of precipitate increases within certain limits with the amount of Water added. The full action of the water also does not take place instantly. Yet it must be borne in mind that not om of these salts is of simple constitution after the type MR and that the products of decomposition are never MO but some new salt of complicated composition.There is this difference too between these cases and all those instances of reci-procal decomposition which are recorded in my paper On the l‘ circumstances modifying the action of Chemical Affinity,” that here a large amount of water many equivalents in fact is required before any trace of the insoluble compound is formed. * According to Scheerer this is 2(3Fe,O,SOJ + 9HO. but the rJpccjmens andjzed by me contained more Rater. DB. GLADSTONE ON THE That the addition of water to a saturated aqueous solution of a salt produces some chemical change is somctimes apparent from a change in colour. Tliis phenomenon was closely examined. It might be anticipated apriori that a certain amount of salt would have the same absorbent ef€'ect on a given number of rays of light whether it were dissolved in much or in little water and that as the absorbent power of water is practically nil it would appear to the eye of precisely the same depth and character of colour in the two cases.And this actually happens in the majority of instances; but to perform the experiment it was of course necessary to make the same quantity of light impinge upon the solution before and after dilution and this required a special con- trivance. Colourless cylindrical glasses of uniform diameter and of the same size were procured and they were each closed at one end with a flat plate of glass. These were placed side by side in a wooden frame (something like that of an ordinary stereoscope) which mas painted black within and so made that it prevented any light from passing into the cylindrical glasses except by the two ends.This frame was supported in such a manner that the glasses were vertical with a space of a foot or thereabouts intervening between them and a sheet of white card-board placed beneath. The glasses so situated mere of course capable of holding solutions and it is evident that the light tratisiiiitted through them to the eye of an observer standing above must come through the flat ends of the cylinders mliicli were of uniform size and equally illumina- tedfrom the white sheet below. It is evident too that any altera- tion in the bulk of the liquid will not affect the quantity of light that enters by the end of the cylinder; and that the fact of all experiments being comparative will eliminate all errors that might have arisen from the difference of light at different hours or any similar cause.As this little apparatus will be frequently referred to I will give it a name and since its principal use is in judging by the eye of the quantity of colour in two solutions it may be appropriately designated the Isoscope. For the purpose c\f determining whether the addition of water to a saturated solution of a salt causes it to absorb more or less light the solution to be examined was diyided equally between the two cylindrical glasses so that when they were looked through from above they appeared identical in colour ; water was then added to one of them and if any change was effected by it it became at once visible by comparison with the other.It was found neces- CHEMICAL ACTION OF WATER ON SOLUBLE SALTS. 41 sary to avoid focusing the eye at any particular part of a solution when diluted so as to be very deep but a little practice will soon enable the observer to avoid this especially when the solutions are looked at from some considerable distance (five or six feet) above. them. It is desirable also to place the head in such a posi- tion that the line joining the two eyes shall be at right angles to the line joining the two glasses for if each eye be immediately over one of the glasses a slight fallacy results apparently from the unequal strength of the two eyes.The accuracy with which slight. differences in intensity of colour may be observed varies with the nature of the colour the degree of illumination and doubtless the sensitiveness of the observer’s eye. In my case I can generally detect under ordinary circumstances a variation of 1 in 50. Differences in the character of the colour are of course easily recognized. In this manner the saturated solutions of many simple salts were examined and where the saturated solution was too intensely coloured to be practically available a slightly diluted solution was placed in each glass and with one of them additional water was mixed. The following salts appeared to be unaffected by water as to their power of absorbing the rays of light :-Ferrous sul ph ate.Terchloride of gold. Ferric nitrate. Terbromide of gold. Ferric meconate. Protochloride of platinum (in Ferric comenate. hydrochloric acid). Ferric cornenamate. Bichloride of platinum. Ferric gallate. Bichloride of palladium. Nitrate of nickel. Chromate of potash. Nitrate of cobalt. Ferrocyanide of potassium. Sulphate of copper. E’erridcyanide of potassium. Chloride of chromium. Nitroprusside of sodium. Acetate of chromium. Sulphindigotic acid. Chromate of chromium. Sulphiridigotate of ammonia. Nitrate of uranium. Carbazotate of copper. Chloride of uranium. Pentasulphide of potassium. Sulphate of ceric oxide. Some dissolved salts were found to vary in the intensity of their colour but not in the character of it on dilution thus :-Ferric acetate became considerably darker.Ferric tartrate became slightly paler. ChroEic sulphate (green modification) became paler. Dlt. GLADSTONE ON THE Many dissolvcd salts were found to vary in the character of their colour according to the state of dilution thus :-Ferric chloride becomes more yellow that is to say passes from a red orange to an orange yellow Ferric citrate becomes paler and more yellow. Ferric sulphocyanide changes from an intense and pure red to orange and on further dilution to yellow ;but when this colour makes its appearance :f decomposition manifests itself by the formation of a yellow precipitate.* Chloride of nickel passes froni a yellow to a blue green. Iodide of nickel suffers a similar change though when strorig it does not transmit so much light as the chloride does.Chloride of cobalt becomes paler and of a more decided pink. Iodide of cobalt passes from a deep green to pink. Acetate of cobalt becomes slightly paler and assumes somewhat of a yellower tint. Sulphocyanide of cobalt passes from a magnificent purple Mue through every shade of purple till it becomes of the ordinary red or pink colour of cohlt salts ill solution. Chloride of copper passes from green to blue. Bromide of copper suffers a similar change. Acetate of copper becomes much paler and passes from a greenish to a more pure blue. Permanganate of potash becomes paler arid of a redder purple. Chromic acid passes from red to an orange brown then to a purer orange wbich becomes paler 011 further dilution.That these changes of colour are due to the action of the water and not to any merely physical cause is proved by the fact that dilution with alcohol does not occasion them. Chloride of copper for instance dissolves in absolute alcohol of a bright green colour and chloride or sulphocyanide of cobalt of a magnificent bluish purple but when examined by the isoscope these solutions are found to be unaffected by the additions of more absolute alcohol either in respect to the intensity or the character of their colour. Ifwater be added to the alcoholic solution the change of colour ensues more or less perfectly according to the relative amount of the two liquids; and if alcoliol be added to a somewhat dilute * This decomposition has cbeen invcstigated by Dr.Claus; see Annal. Chem. u. Pharm. July 1856. He seems to be unaware that the sulphocyanide may be diluted till it appears of a yellowish orange without any precipitate forming even after many dap. CHIZNICAL ACTION OF WATER ON SOLUBLE SALTS. 43 aqueous solution of these salts the primary colour is more or less restored. Ferric sulphocyanide however seems to form an excep- tion. A very large quantity of absolute alcohol produces the same change in the colour of this substance that a much smaller quan- tity of water does and on long standing a little yellow substance separates. I do not believe that this depends on any water in the alcohol itself; for that employed by me was of specific gravity 790 and it is bard to conceive that any trace of water should leave the strongest alcohol to act upon a salt and effect a change which usually requires its presence in overpowering quantity.A glance at the list of salts which change colour on the addi- tion of water mill suffice to show that they consist of little else than acetates and a peculiar group of "haloid " salts namely compounds of chlorine bromine iodine and sulphocyanogen with iron and the allied metals nickel cobalt and copper. These changes of colour though consistent with the idea of the water added to a saturated solution decomposing more of the original salt MR and thus forming inore MO,HR are very far from proving that hypothesis. They may be attributed to the formation of a higher hydrate; and other hypotheses might easily be invented.It seemed however a matter of interest to try whether the change of colour producedby water in a solution of such a salt as acetate of copper was analogous to the change that takes place on the addition of another hydrogen compound for instance hydrochloric or sulphuric acid" Now in both cases a reductioii of the colour ensues; and in the case of the acid it takes place in a diminishing ratio that is each addition of acid has a smaller effect (as cornpad with its quantity) than the preceding. Does the action of water exhibit a similar ratio? Experiments were performed to determine this. A portion of a saturated solution of acetate of copper was divided equally between the two vertical glasses of the isoscope.The one was kept as a standard; to the other a known amount of the same saturated solution was added and as that of course increased the colour water was added till it was brought down again to that of the standard. The ratio between the amount of water added and the amount of coloured salt which it could render invisible so to speak gave what was required. Tmexperiments were made with the same solution. * Phil. Tram. 1855 pp. 222 223. DH. GLADSTONE ON THE Orig. aniouir Amount of Witer required. Rcducing effect of each addition of 11 01 of Acetate icetateof Cop Water. Colper Soh per solution tion. added. Exp. I. Exp. 11. Exp. I. Exp. 11. -__I-Yts. Pts. Yts. Pts. Per cent. Per cent.100 8 60 13.3 a. 100 16 116 .. 14.3 100 24 180 *. 12.5 100 32 244 12-5 100 40 .. 330 .. 12.1 100 48 352 14.8 10.7 100 56 .. 6.1 100 64 596 6:5 10. 100 72 .. *. 4-6 100 80 980 975 4 -2 4.3 100 88 .. 1180 .. 3.9 100 96 1500 1440 1 3.1 3.1 Both these experiments indicate that the effect of additional quantities of water is in a decreasing ratio at least after the addi- tion of four or five times its bulk of water to the saturated solution about which point the two experiments show a certain irregularity and discrepancy. About this point also the change to a somewhat purer blue takes place. On mixing water with a solution of ferric acetate the colour is considerably deepened but on standiug awhile the solirtion becomes nearly as pale as originally.The following series of observations was obtained with ferric sulphocyanide :-I Orig. amount of Ferric Amouiit of Sulphocvanide Water required. Reducino effect of each Sulphocyanide Solution. Solution added. addizon of Water. ---_I_-_-_p-_ Pts. Yt,s. Pts. Per 100 pts. 100 10 24 4.2 100 20 44 5.0 100 40 ao 5.5 100 60 128 4.2 100 80 204 2.6 100 100 296 2.2 100 120 384 2.3 100 140 46a 2.4 100 160 556 2.3 100 190 692 2.2 The irregularity of these results rather militates against the idea of water acting on salts in the same way as a hydracid A still stronger argument against this hypothesis was found on a comparison of the rays absorbed by dilute and strong solutions of those salts that vary in the character of their colour according to the amount of water.It invariably happens that the dilute solutioiis while they transmit every ray that was transmitted by a strong solution of the same salt transmit also some that were absorbed by it. To take a particular instance blue sulphocyanide of cobalt absorbs at once those rays of the prismatic spectrum which lie about the fixed line D; the red sulphocyanide transmits them perfectly hence it may be concluded that after a certain dilution no more blue sulphocyanide is left a conclusion at variance with the supposition that HO acting on CoCsy (blue salt) produces Co0,HCsy (red salt) + HO + CoCsy the amount of the last substance diminishing as the water incrcases but never entirely disappearing.The nature of the absorption indicates rather that the strong solution contains the compoixnds present in the dilute solution plus some other; arid a close prismatic examination of the 'haloid ' salts that change colour has furnished me with a remarkable confirmation of this view. It is founded on the fact deduced by apriori reasoning in my paper on the use of the prism,* and demonstrated in a more recent paper,? that ('when two bodies combine each of which exerts a different influence on the rays of the spectrum the one constituent will absorb certain rays and the other certain other rays and the dissolved salt itself will transmit only those rays which are not absorbed by either or in other words only those which are trans- mitted by both." Now strong solutions of ferric chloride chloride and bromide of copper chloride and iodide of nickel and of cobalt exhibit not only the absorption due to the respective metals but another absorption which can be identified with that produced by the halogens themselves when simply dissolved in water ; while when these solutions are diluted they cease to produce this second absorption and give precisely the same prismatic image as any compound of the same base with a colourless acid.This is explained in detail with figures in the paper already referred to.? It is certainly a suggestive fact and shows I think most clearly that there is some difference of' arrangement among the elements of the dissolved salt and the water according to their proportional * Quart.Journ. Chem. SOC.April 1857. 't Phil. Mag. Dec. 1857. DR. GLADSTOXI3 ON THE amount and the degree of temperature; but wliat is that diffe- rence? The peculiar absorbent power exerted by bromine shows itself in the green solution of bromide of copper but there is certainly no free bromine present and it will hardly avail us to suppose that such a solution contains the true CuBr and that the change of colour on dilution arises from the formation of a compound of oxide of copper with the colourless hydrobromic acid; for there would still remain the question-why should bromine affect the light mheri in combination with copper while it does not do so when combined with hydrogen or potassium or indeed any other metal beyond this particular group and the congeners of gold ? Besides anhydrous bromide of copper which certainly has the greatest claim to be considered CuBr is not green but black.DOUBLE SALTS. The action of water on douhle salts is a still more complicated problem for beside all the questions that arise in respect to simple salts there is the additional inquiry -whether water separates the two constituents of which the double salt is composed. This latter question however is more capable of decisicn than some previously discussed. That a double salt is not always resolved into the two simple salts which we suppose constitute it requires no elaborate proof. The iodide of platinum and potassium dissolves easily in water though the iodide of platinum itself is insoluble; while on the other hand the potassio-chloride is sparingly soluble though each of the chlorides supposed to be contained in it dissolves readily in water.It is very conceivable however that in some cases a partial decomposition may take place ; indeed some of Professor Graham’s experiments seem to indicate this. He states,* that when alum or bisulphate of potash is diffused one of the constituents passes out of the cell in greater quantity than the other. Now if these double salts are partially decomposed by the water this is precisely what might be anticipated; and there is nothing else than water present to decompose them. Should water exert such an action it might be espected that the action would be increased by the addition of more water.* Phil. Trans. 1850,p. 19. CHEMICAL ACTION OF WATER ON SOLUBLE SAT,TS. 47 There are cases in which water when added in above a certain amount does decompose a double salt. Thus colourless crystals of the iodide of mercury and potassium will dissolve in a little water but the addition of a larger quantity causes the separation of the insoluble yellow iodide of mercury; and water added to a saturated aqueous solution of sulphocyanide of silver and potassium gives a curdy precipitate of sulphocyanide of silver.% In each case the more water is added the mgre complete the dec3mposition. As double salts in a crystallized condition sometimes differ considerably in colour or shade from the simple salt of that base to which the colour is due it was thought that if an increasing decomposition by water took place it would make itself visible by a change of colour or shade when a strong solution was diluted in the isoscope.It was fouud however that the solution of a double salt cmtaining a coloured constituent has generally spsaking precisely the colour and shade of that constituent ; thus 200 grms. or one equivalent of crystallized sulphate of copper and ammonia gives precisely the same chromatic appearance when dissolved in water as 123 grms. or one equivalent of crystallized sulphate of copper. Thus it was impossible to derive any information from the fact that a solution of that salt or the corresponding potash salt or potash chrome alum or the sulphate of nickel and potash did not change in colour when diluted.The double chloride of platinum and potassium the double iodide of the same the analogous gold salt and the hydrochlorate of chloride of gold are also unaffected in colour by the further addition of water. What is more to the point is this-that the red bicliromate of potash does not pale in colour on dilution or become more yellow as would be the case wae more of the free acid and the neutral potash salt formed; and the Xcomenamate of iron which is red remains unchanged although the neutral salt is purple and the cornenamic aciditself colourless. On the other hand instances are not wanting of double salts the solutions of which change colour on dilution. Thus the corn- pounds of' chloride of copper with chloride of sodium chloride of ammonium chloride of platinum or hydrochloric acid though green when dissolved in the minimum of water become blue on dilutioii just as chloride of copper itself does; but they require a larger amount of water to produce the change than is requisite in the case of the simple salt.Red potassio-chromic oxalate varies * Described by Gissman Ann. Pharm. Oct. 1856. DR. GLADSTONE ON THE in intensity of colour by dilution becoming sometimes paler and at other times darker. The strong solution of white iron alum becomes redder on dilution and Rose * has shown this to be due to the formation of a slightly soluble basic salt. If a double salt be resolved on solution more or less into its simple salts each of these will assuredly obey the law of reciprocal decomposition with any other salt that may be present.That this reciprocal action does take place between an ordinary and a double salt is beyond question; but that the elements of the latter have separated to produce it is not so easily ascertained. One form of the experiment however occurred to me that seemed to be of a somewhat crucial character. Acetate of copper is of a much deeper blue than an equivalent amount of the sulphate and this last as stated above is identical in colour with the double potash salt. If on mixing the sulphate of copper and potash with the acetate the double salt should preserve its inte- grity it is not very easy to conceive of a reciprocal decomposition for the acetate itself is strictly rnonobasic but if the double salt should separate to any extent the free sulphate of potash will certainly suffer reciprocal decomposition with the acetate of copper and as a portion of the copper will then be combined with sul- phuric acid a reduction of the colour will ensue.Accordingly two equal portions of acetate of copper solution were mixed in the isoscope the first with an equivalent of sulphate of copper the second with an equivalent of double sulphate of copper and potash. The second mixture appeared somewhat lighter in shade than the first and on the addition of three equivalents to each the second became of a distinctly purer and paler blue. A similar experiment was made with the intensely scarlet bromide and the pale yellow hydrochlorate of the chloride of gold.The addition of the latter compound reduced the colour of the bromide though of course the mixture contained a larger amount of gold than the scarlet solution. It may be objected to this reaction that there probably exists a hydrobromate of the bromide of gold analogous to the chlorine compound; but that will not account for the reduction of colour since the addition of hydrobromic acid to the neutral bromide does not render the solution paler. In respect then to double salts it may be concluded that some are resolved by water more or less into two distinct salts while * Pogg. Ann. ixxxiii 132. CHEMICAL ACTION OF WATER ON SOLUBLE SALTS. 49 others preseri-e their integrity in solution ;bnt what determines this difference does not yet appear.In respect to the general question of the chemical action of water on a soluble salt I feel that no satisfactory conclusion has yet been arrived at ; the idea that a reciprocal decomposition takes place between the two compounds has received no confirmnt'ion from my inquiry unless in exceptional cases. The results ra$lzer militate in my opinion against that supposition and tend to con-vince me more and more that the actual state of a dissolved salt is beyond the expression of any of our formula VOL XI. E

ISSN:1743-6893    

DOI:10.1039/QJ8591100036

出版商:RSC    

年代:1859

数据来源: RSC

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PROCEEDINGS AT THE MEETINGS OF THE CHEMICAL SOCIETY. January 2lst 1858. Dr. LYONPLAYFAIR, C.B. President in the Chair. The following Gentlemen were elected Fellows of the Society:- Arthur Nield Esq. Bowdon near Manchester. ICichard Rumney Esq. Ardwick Chemical Works Man-Chester. Daniel Hanbury Esq. Plough-court Lombard-street. Dr. Daubeny read and commented upon a communication he had received from Baron Lie b ig relating to some experiments he had'made on the absorptive power of soils in continuation of Professor Way 's experiments. Dr. Daubeny also brought under the consideration of the Society the experiments of TiC'ohler and Deville on the direct formation of nitride of titanium by the ignition of metallic titanium in air or nitrogen and suggested that the source of volcanic ammonia might be a nitride of a similar description that of boron for instance which by the action of steam would be resolved into boracic acid and ammonia.Dr. Hofmann exhibited and described an improved form of gas-combustion furnace whicth he had recently had constructed ; in this furnace the gas is burnt from numerous small openings in clay cylinders which thereby become red hot so that as in the original charcoal furnace the combustion tube is surrounded by ignited solid and the supply of oxygen or air from gasometers is rendered unnecessary. Dr. Frankland also exhibited a combustion furnace which had been arranged by Professor Von Babo. In this furnace the gas PROCEEDINGS OF THE CHEMICAL SOCIETY.was burnt in a series of modified Bunsen’s burners; the combus-tion tube was surrounded by ignited solid and the stopcocks were replaced by keys resembling those of a musical instrument. A paper was read :-“On the chemical action of Water on soluble Salts;” by Dr. Gladstone. February 4>1858. Dr. LYONPLAYFAIR, C.B. President in the Chair. The following donations mere announced :-“The Journal of the Geological Society :” from the Society. “ Proceedings of the Liverpool Literary and Scientific Society :” from the Society. “The Pharmaceutical Journal :” from the Editor. ‘‘ The Journal of the Society of Arts :” from the Society. The following were elected Fellows of the Society :-F. A. Manning Esq. 54 Archer-street Paddington.P. J. Worsley Esq. 4 Tabiton-street Gordon-square W. E. Squire Ph.D. 277 Oxford-strcet. J. F. Watson M.A. M.D. 51 Archer-street Kensington- park W. Dr. Hofmann described some experiments in which he had been recently engaged upon poly-atomic ammonias. February 18 1858. Dr. LYONPLAYFAIR, C.B. President in the Chair. The following were elected Fellows of the Society :-T. H. Henry Esq. 44 Lincoln’s-inn-fields. J. Augustus Matthiessen Ph.D. 1 Torrington-street. A paper was read :-“ On the Iodo-sulpliates of the Cinchona Alkaloids t’ by Dr W. Bird Herapath. E2 March 4 1858. Dr. LYONPLAYPAIR, C.B. President in the Chair. The following were elected Fellows of the Society :-Sir Robert Kane F.R.S. Dublin. J. T. Hobs on Esq.Ph.Z). 34 Cleveland-square Hyde-park. W. Thornwaite Esq. 123 Regent-street. The meeting was then adjourned to enable the Members to attend the Bakerian Lecture at the Royal Society. March 18 1858. Dr. LYONPLAYFAIR, C.B. President in the Chair. The following donations were announced :-“Catalogue of the Antiquities in the Museum of the Royal lrish Academy.” “ Recherches sur la diffusion du Fluor par M. J. N ickles.,’ “Transactions of the Royal Scottish Society of Arts.’ “ Kritische Zeitschrift fkr Chemie Physik und Mathematik.” The following were elected Fellows of the Society:- John Purdue Bidlake B.A. 9 Upper Barnsbury-street Islington. Edward Dalziell M.D. F.R.S.E. Edinburgh. Alexander Goaler B.A. The College Hurstpierpoint Sussex. Thomas Hyde Hills Esq. 338 Oxford-street. Henry Wollaston Hutton B.A. Spordlington Market Raisen Lincolns hire. D avid 0ldfield Esq. Boscombe Lodge Finchley-road. The following papers were read:- “On the action of Bromine on Acetic Acid:” by Messrs. Perkin and Duppa. ‘‘On a Poison obtained from Arrows-” by Mr. Henry Hancock.

ISSN:1743-6893    

DOI:10.1039/QJ8591100050

出版商:RSC    

年代:1859

数据来源: RSC

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NOTICES OF PAPEM CONTAINED IN OTHER JOURNALS. Extract of a Leiter from Baron Liebig to Dr. Daubeny dated December 25 1857.* u I BAVE published a series of experiments on some properties of soils by Ghich I think I have completed the researches instituted by Professor Way respecting their capacity for absorbing the soluble constituents of manures. "My experiments were limited to those constituents which are presented to plants from natural sources and to the conditions necessary for rendering them soluble and absorbable by the roots. 'c I was a little astonished to find that the cause of this solubility did not appear to be traceable to circumstances attributable to the plant itself but that something inherent in its own organization must co-operate with the actual conditions in which it was placed in order to enable it to extract its food from the ground.''The potassa belonging to silicate of potassa is absorbed by all kinds of soil but not so the silicic acid accompanying it. If a solution of silicate of potassa be brought into contact with soils rich in organic matters the potassa is absorbed but the silica remains in the solution. "From a solution of phosphate of lime or of phosphate of mag- nesia in water saturated with carbonic acid soils absorb the phosphoric acid whilst they allow the lime still to remain in the solution. ((Thus the inference deducible from my experiments is that land plants do not receive their food from a solution of the ingredients already present in the soil but that they abstract or absorb it directly from the soil itself through the joint agency of water and of'a force inherent in their roots.'' Sometimes we find stones in meadows covered over with striae exhibiting a kind of network which is produced by the corrosive action of the roots of plants in contact with them. '(It has hitherto been assiimed that a plant possessed a decom-posing power as well as a secreting one. Thus when the potassa of sulphate of potassa or the potassium of the chloride became associ- ated with the vegetable organization we supposed that the salt had been decomposed within the plant and the sulphnric acid or chlorine eliminated by it. This power does not exist. The salts Communicated by Dr. Daubeny. EXTRACT OF A LETTER in question are decomposed by the soil and the plants all receive their food from elements in the same state of combination.“The experiments of Way constitute the foundation of a new theory of vegetable nutrition. “I moreover find that plants living in fresh water receive their food in the very same way as those which are marine. I examined the Zemna trisulca which grows on the surface of stagnant water a plant containing 16.6 per cent. of inorganic matter. I compared the analysis of its ash with that of the water in which the plant had grown from which it appeared that the plant and the water contain the same constituents but in very different proportions ; thus the ashes of the plant contained in 100 parts 16-82 of lime whilst the salts present in the water in 100 parts contained 35.00.Again the ashes contain . . 5 of magnesia the salts in the water . 12 Y, the ashes . . 13 of potassa the salts in the water about 4 , “Just then” (as I interpret Baron Liebig’s meaning) ‘(as algae absorb from sea-water the small quantities of iodine and of potassa present in it without regard to their amount as compared with other constituents so the lemna appears to do the same with respect to the constituents above cited a power of selection residing in the roots being in both instances evinced ‘‘ There is perhaps,” continues Baron Liebig (‘no mineral spring in the world which contains the amount of soluble salts present in stagnant waters. Compare for instance with a mineral spring the water of the River Thames that of the springs analysed by Hofmann Moller and Graham and that of the water (drain water) examined by Way which had drained through soil.Thus Thames water contains from 1.3 to 7.3 per-centage of potassa according to the spot from whence it is taken being richest in potassa where it had received the largest amount of animal matter as at Lambeth. In well-water the potassa it varies from 0.7 to 6.0 per cent. whilst not more than a trace is found in water which has drained through soil. “Owing to the eremacausis and decay of the many generations of plauts which have existed in stagnant waters their organic matter is resolved into compounds of oxygen (becomes oxygen- ated) and their inorganic constituents remain dissolved in the water itself thus rendering it rich in substances which are never found in equal proportions in the water of springs and rivers.” Such is the substance of Liebig’s letter to me with only siich alterations as I have thought proper to make in it in order to render his meaning more intelligible although in general the Baron’s English style is so good as to require but little correction.In the German paper he has likewise sent me a FROM BARON LIEBIG. reprint as I imagine of an article of his inserted in the AZZgemeine Zeitung more details are given and some facts added in corrobo- ration of the views which I have brought Before you. The experiments cited need not perhaps detain us as they do little more than confirm the conclusions arrived at by Professor Way with which we are already familiar.It does not appear however whether he adopts the view at present taken by Mr. Way namely that the retention of the alkaline ingredients by the soil is connected with an interchange of elements the salts of lime for instance being carried down with the acid whilst potasaa unites with the carbonic acid set at liberty. Be that however as it may the inference which Liebig draws remains unaffected; for it is evident that granting this to be the fact an affinity must be exerted by the soil for the newly-formed salt in order to prevent its being carried away by the water which percolates through it and being present in the drainage. Now what is this affinity? Liebig compares it to that which enables charcoal to retain the colouring matter of liquids within its pores or that which causes starch to unite with iodine ;but in any case something more than the action of water is necessary to overcome it or the new salts could not remain in the fallow for any time after they had been formed.This assisting force Liebig considers to reside in the roots and there are certainly many facts which tend to show that these organs operate not merely passively by imbibing any liquid that happens to present itself to them but that they possess an active and as it were a vital energy in absorbing some substances and in eliminating others. This indeed is precisely the same conclusion which I had myself arrived at so long ago as the year 1833 from experiments in which plants were watered with salts of strontia without absorbing any appreciable quantity of that earth; as will be seen by my Paper ‘‘On the Degree of Solution exercised by Plants with regard to the Earthy Constituents presented to their Absorbing Surfaces,” which was published in the Transactions of the LinnEan Society for that year.We may also thus explain why plants may be watered as has been done by myself with weak solutions of arsenic without being themselves affected or contracting therefrom any poisonous property; nor is this inconsistent with the fact that certain poi- sonous solutions such as the salts of copper or iron do find admittance into the tissue of plants because in these instances the vitality of the roots is in the first instance destroyed and thus the imbibition of the poison takes place as would occur even in dead matter by endosmose and by capillary attraction.It is at least certain that the water which trickles through a bed of soil contains far too small a proportion of the ingredients which the crop contains to be regarded as the source from whence HOFMANN AND CAHOURS the latter can obtain them as Baron Liebig has shown by a very simple calculation; and hence we are driven to attribute them to the constituents which Professor Way's researches have shown to be separated by and combined with the soil. Now as the latter will not impart them to water alone except in very small quan- tities it is at least evident that some power must reside in the roots which can assist in overcoming the chemical affinity between the soil and the inorganic matters which the plant assimilates.Such at least appears to be the conclusion to which Baron Liebig has arrived and as no notice seems to have been yet taken of his researches in any English Periodical I trust I shall be par- doned both by him and by the Society in thus bringing forward the substance of a private letter in which a short abstract of them is contained. Researches on the Phosphorus-Bases. By Augustus William Hofmann and Augustus Cahours. Abstracted from a Paper read before the Royal Society June 18. 1858. INa note on the action of chloride of methyl upon phosphide of calcium communicated more than ten years ago to the Institute of France,* M.Paul Thbnard pointed out the existence of a series of bodies which correspond to the compounds of phosphorus with hydrogen which may in fact be viewed as hydrides of phos- phorus the hydrogen of which is replaced by an equivalent quantity of methyl. One of these bodies a liquid possessing a most offensive odour spontaneously inflammable and explosive in the highest degree corresponds to the liquid phosphoretted hydrogen and appears to occupy in the phosphorus-series the same position which belongs to kakodyl among the arsenic-compounds. It is a colourless somewhat viscid liquid which boils at about 25OOC. Exposed to the slow action of the atmosphere this liquid is converted into a compound which is strongly acid and easily crystallizes.This acid is probably analogous to kaliodylic acid. In addition to this liquid body two solid substances are formed by the action of chloride of inetlipl upon phosphide of calcium. One of these according to M. Paul Th~narcl,corresponds to the solid phosphoretted hydrogen whilst the other which is the prin- cipal product of thc reaction constitutes the hydrochlorate of a very volatile phosphoretted base. From its composition this body may be viemd as ammonia in which the nitrogen is replaced by * Comptes Rendus t. xxi. 1). 1-14 and t. xxv. p. 892. RESEARCHES ON THE PHOSPHORUS-BASES. phosphorus whilst methyl is substituted for the hydrogen. When repeating these experiments in the ethyl-series Paul Thd nard arrived at similar results to which he however only briefly allides.At the time when these experiments were first made the ammo- nia-bases had not been discovered aud the subject presented obstacles so numerous and varied that the researches of this chemist remained unfinished. Nobody will be surprised at this who has made himself acquainted with the difficulty of effecting the above-mentioned reactions and who from his own experience knows the danger which attends the preparation of these com- pounds and the horrible odour which some of them possess. Paul Thgnard’s remarkable researches did not excite at the time of their publication that degree of interest which they really deserved. There were hut few facts known at that period with which his resiilts could naturally be connected ; indeed until after the ammonia-bases were discovered the importance of the experiments on these phosphorus-bodies could scarcely be recog- nized ; then it was that M.Paul Thknard’s investigations attracted that attention to which they were entitled; then it was that the remarkable pzcrallelism of the compounds of phosphorus and nitrogen more and more distinctly cxhibited by these discoveries began to become an object of general interest to chemists. It is now many years since 14. Paul ThGnard abandoned the study of the phosphorus-compounds for the first knowledge of which we are indebted to him. The unfinished state in which these researches remained arid the rich and abundant harvest collected since that period in all the neighbouring fields of science necessitated a revision of the subject.Thc discovery of methyla- mine dimethylamine ad trimethylamine and of the correspond- ing terms in the ethyl- and azmyl-series had shown that the hydro- gen in ammonia may be replaced by binary molecules such as methyl ethyl amgl and phenyl the newly-formed compoirnds retaining the basic character of the original ammonia-molecule ; whilst the production of triethylstibine and triethylarsine had furnished the proof that the total replacement of the hydrogen in the indifferent antimonietted and arsenietted hydrogen exalts the chemical character of these compounds in a most remarkable man- ner the methylated and ethylated lsodies exhibiting basic charm- ters scarcely inferior to those of ammonia itself.It remained therefore to be investigated whether phosphorus which by its chemical tendencies stands between iiitrogen and arsenic would exhibit a similar deportment. It remained to be ascertained in what manner the gradual entrance of binary molccules in the place of the hydrogen in phosphoretted hydrogen mould change the character of the original compound. The discovery of the tetrethylated ammonium-bases had also opened a new fie-d of research in which the corresponding terms of the antimony- and IIOFMANN AND CAHOURS ON THE arsenic-series were rapidly brought to light. It was indeed pos-sible to predict with certainty that an appropriately selected method would lead to the production of the analogous derivatives of phosphoretted hydrogen.The time for resuming the study of the phosphorus-bases had in fact arrived. We have been engaged for a considerable time in the investi- gation of this subject and now beg to offer to the Royal Society in the following pages an account of our experiments. In the first place we have endeavoured to obtain the bases corresponding to phosphoretted hydrogen by a method analogous to that followed by M. Paul The'nard. Recent experience suggested at once the replacement of the gaseous chloride of methyl by the liquid iodide which is so much more convenient for experiment ; and also the substitution for the phosphide of calcium of the compound of phosphorus and sodium obtained by the direct union of the elements.On the application of heat these substances act on one another with great energy producing combustible and detonating compounds so that the experiment is not without danger. Often the product of the operation is lost; and if the reaction has taken place without explosion the separation of the constituents of the very corn-plicated mixture which results can be effected only with the greatest difficulty. We have convinced ourselves that the product of the action of iodide of methyl upon phosphide of sodium consists chiefly of three different substances viz ,of a liquid which probably is Me I? and corresponds to kakodyl; of a second liquid Me P corresponding to trimethylstibine and trimethylaraine ; and lastly of a beautiful crystalline solid body hle,YI which is the analogue in the phos- phorus series of iodide of tetrametliylammonium.We abstain from a minute description of the experiments made in this direction since in the further course of the inquiry we have forsaken this method altogether. Indeed this mode of preparation is very uncertain and the separation of the products formed is attended with almost insurmountable obstacles not to speak of the difficulty of obtaining pure phosphide of sodium fit for the reaction. The question resolved itself into the discovery of a method which would yield us the desired substances conveniently without danger in considerable quantity and in a state of absolute purity. It appeared to us that the action of terchloride of phosphorus on zinc-methyl zinc-ethyl &c.would enable us to attain the desired result. Experiment has fully confirmed this anticipation. Dr. Frankland's remarkable observations on the action of zinc upon iodide of methyl and iodide of ethyl at high temperatures are still fresh in the memory of chemists. Besides the hydro- carbons methyl and ethyl zinc-methyl and zinc-ethyl are formed in this reaction which exhibit the deportment of true organic RESEARCHES ON THE PHOSPHORUS-BASES. metals comparable in the intensity of their combining powers with the most electro-positive elements. In the action of a chlo- ride upon such a compound metal the chlorine was sure to seize upon the zinc and it was extremely probable that together with chloride of zinc methyl- or ethyl-compounds would be formed in definite proportions.In the action of terchloride of phosphorns the formation of a methyl-or ethyl-compound of phosphorus corresponding in composition to the terchloride of phosphorus might be with certainty expected PC1 I-3llleZn = 3ZnC1 + Me,P. These anticipations were in fact fulfilled. The products of these reactions the bases Me,P and E3P which we propose to call respectively trimethylphosphine and triethylphosphine remain nnited with chloride of zinc and simple distillation with an alkali is all that is necessary to liberate them 3ZnC1 Me,P + 6K0 = 3KC1 + 3(KO ZnO) + PMe 3ZnC1 E Y + GKO = 3KC1+ 3(KO ZnO) + PE,. They are obtained in this way as volatile oils with a peculiar and strongly-marked odour and possessing distinct basic properties We found no difficulty in procuring the bodies in question by this method in a state of perfect purity so as to examine their properties with accuracy.From the outline which we are about to give it will be obvious that this group of bodies exhibits the most striking analogies with the ammonia-bases so much so in fact that frequently it will only be necessary to repeat the observations which were published by one of us about eight years ago regarding the methylated and ethylated derivatives of ammonia.* The experiments which we have to communicate refer chiefly to the methyl- and ethyl-compounds; though here and there we have used amyl as material. Since we have preferred working in the ethyl-series we begin with the description of the ethyl-compounds.EXPERIMENTS IN THE ETHYL-SERIES. Action of Terchloride of Phosphorus on Zinc-ethyl. The reaction between these two bodies is very violent and readily gives rise to dangerous explosions if the necessary precau- tions are iieglect.ed. We have generally adopted the following arrangement. A tubulated retort is joined to a receiver which in its turn is connected with a wide glass tube bent at an angle of * Philosophical Transactions 1850,F. 93; 1851 p. 367. EOFWA" AND CAHOURS ON THE about 70° and acts like a second receiver. The angle of this tube is filled with terchloride of phosphorus and the tube is con-nected with a large cylinder which is supplied by a suitable appa- n Apparatus for generating carbonic acid.6. Wabh bottle containing sulphuric acid. c. Reservoir of carbonic acid. d. Bent tube containing terchloride of phos-phorus e. Receiver. f.Retort containing zinc-ethyl. 9. Dropping apparatus filled with terchloride of phosphorus. ratus with dry carbonic acid. As soon as the carbonic acid has expelled the air from the reservoir tube receiver and retort an exit-tube from the reservoir up to that time closed by a caoutchouc cap is opened to let out the carbonic acid the evolution of which is maintained during thc whclc operation. The tubulaturc of the retort is now connected with the copper digcster in which the zinc-ethyl has been prepared ; and as soon as the retort has received a charge of the ethereal solution of zinc-cthyl therc is fixed into the same tubulaturc a little dropping apparatus consistLig of a glass globc aith a tubulature and stopper at the top and termi- nating below in it glass tube iii which a stopcock is fitted.This apparatus is filled mith terchloride of phosphorus and by appro-priately adjusting the stopcock and opening or closing the stopper of the glass globe any desired flow of the fluid can be maintained with the greatest nicety. However slowly thc action may be accomplished md holierer well moreover the retort and receiver may be coolcd by water or ice the action is nelertheless invariably so ~iolent that all the ether and with it a large quantity of the zinc-ethyl passes over iiito the receiver. By the powerful ebullition which periodically ensues a portion of' the vapour is driven even into the bent tube and a considerable loss of zinc-ethyl is incurred unless this tube be filled with terchloride of phosphorus which greedily absorbs every trace of the former compound.This fluid valve ascending and descending in the tube in accordance with the progress of the reaction regulates the function of the apparatus so perfectly that the operation which always takes several hours when once begun continues by itself. Sometimes the absorption is so violent that the terchloride of phosphorus in the tube is sucked back into the receiver but even then no loss is to be feared since the tube is connected with the reservoir filled with carbonic acid. The first drops of terchloride of phosphorus which fall into the solution of zinc-ethyl hiss like water when brought in coiitact with red-hot iron.The action becomes by-and-by less violent and as soon as an evolution of heat is no longer perceptible the operation is tcrminated. There remain in the retort in the receiver in the bent tube and sometimes even in the carbonic acid rescrvoir two liquid layers,-the one a heavy pale straw-coloured thick fluid the other a transparent colourless mobile fluid floating on the former. The heavy fluid a compound of the phosphorus-base with chlo- ride of zinc nearly solidifies on cooling but the viscid transparent mass exhibits no trace of crystallirie structure. The light fluid is a mixture of ether with an excess of the terchloride of phosphorus; after disconnecting the apparatus it is poured off from the viscous fluid and may be used after distillation in a second oper a t’ion.Some ether and terchloride of phosphorus which may still adhere are expelled by gently heating the retort upon a sand bath. In order to liberate the phosphorus-base from its combination with zinc nothing more than a distillation with potassa is required. To prcveiit the destruction of the retort to which the zinc-com- pound adheres with pertinacity and tlie loss of so precious a mate- rial this operation is conveniently performed in the following maimer. Solid hydrate of potassa is placed on the hard resinous cake attached to the bottom of the retort and a slow current of water allowed to flow in by the dropping apparatus after the air in the retort has been carefully displaced by hydrogen the heat evolved during the reaction is quite sufficient to volatilize the base with the vapour of the water ;it may be condensed by an ordinary cooler.The base which is now floating on the water of the distil- late is removed by means of a separating funnel; it is allowed to stand for a day over hydrate of potassa and finally rectified in a current of dry hydrogen gas. Triethy~hos;uhine.-Thus obtained triethylphosphine is a colour- less transparent mobile liquid which strongly refracts light. Thc compound is lighter than water its specific gravity being found to be 0-812at 15O.5 C. ;it is perfectly insoluble in water but soluble in every proportion in alcohol and ether. Its odour is penetrating almost benumbing but still not disagreeable.The intolerable smell which renders it so unpleasant to lyork with these phospho- rus-compounds generally arises from other products which make their appearance in considerable quantitics,. especially in preparing HOPMANN AND CAHOURS ON THE the phosphorus-base by means of phosphide of sodium and iodide of ethyl. In a diluted state the odour of the pure triethylphos- phine has the greatest similarity to that ofthe hyacinth.* Long-continued working with this substaiice causes headache and sleeplessn eas. The boiling-point of the triethylphosphine is 127O.5C. under the barometric pressure of 0.744m The determination was made with an ounce of the pure substance. The distillation of the phosphorus-base must be performed in a stream of dry hydrogen for it attracts oxygen with great energy especially at high tem- peratures.It is impossible to pour the liquid from one vessel into another without its becoming perceptibly warm. The product of oxidation formed in this way becomes evident in the last stage of the distillation. When the larger quantity of the base has dis- tilled over the mercury in the thermometer begins suddenly to rise and before the temperature has become again stationary the neck of the retort is found to be coated with a network of beautiful crystals which are even drawn over into the receiver. These crystals are permanent as long as they are protected from the action of the moist air. After disconnecting the apparatus it is vain to attempt to collect the crystals the most minute quantity of water causing them to liquefy to a heavy oil soluble in water.From these remarks it is obvious that triethylphosphine must be almost always contaminated with a sniall quantity of this sub- stance; in fact a bottle containing the base cannot be opened without its being formed. When the phosphorus-base is brought in contact with oxygen vapours are immediately formed ; the liquid frequently becomes so hot that it inflames and the body is burnt with evolution of dense white fumes of phosphoric acid. If a strip of paper moistened with triethylphosphine be introduced into a test-tube containing oxygen and immersed in hot water the vapour of the phosphorus-base produces with the oxygen an explo-sive mixture which detonates after a few moments with consider- able violence.With atmospheric air a similar detonating mixture is formed which explodes at comparatively low temperatures. To avoid serious accidents the phosphorus-base should always be dis- * There is nothing new in the fact that the odour of a substance may be consider- ably changed by dilution. Several years ago when occupied in the preparation of different ethers which have found numerous applications in perfumery I had frequent opportunities of observing how the desired aroma which was absent in the pure sub-stance was brought out by dilution with alcohol. The hyacinth smell of the dilute phosphorus-base is so characteristic that one morning I found in my laboratory a large basket filled with hyacinths the present of a lady friend of mine who interested in my labours had a strong impression that triethylphosphine must be present in the hyacinth.In the interest of science the entire floral adornment of the garden had been unmercifully sacrificed ! It would have been ungrateful not to distil them but I regret to say that the anticipation of the amiable donor who wished to enrich me with so interesting a discovery proved unfounded. The hyacinth does not contain any phosphorus-base.-A. W. H. RESEARCI-IES ON THE PHOSPHORUS-BASES. tilled in an atmosphere of hydrogen. When poured into a flask filled with chlorine gas every drop of triethylphosphine is inflamed with disengagement of pentachloride of phosphorus and hydrochlo- ric acid and separation of carbon.The phosphorus-base unites with bromine and iodine evolving considerable heat which may give rise to inflammation; but if the action be moderated crystal- line compounds are produced. In cyanogen gas the phosphorus- base is converted into a brown resinous mass. If a piece of sul-phur be thrown into a test-tube containing triethylphosphine it becomes so hot as to fuse the sulphur which then floats on the liquid base in the form of globules as sodium does on water and at last entirely disappears. The clear liquid thus obtained solidifies on cooling to a magnificent crystalline mass. The experiment must be made with caution since the vapour of the phosphorus- compound which rises during the reaction generally explodes on coming in contact with the air contained in the vessel.Selenium gives rise to similar but less powerful phenomena. Although triethylphosphine in its relations to other bodies powessea all the characters of a well-defined base it does not exhibit an alkaline reaction. When freshly prepared it is without action on vegetable colours but when exposed only for a few moments to the influence of the air it begins to show a con-stantly increasing acid reaction. Triethylphosphine unites with acids slowly but with considerable evolution of heat ; with con- centrated acid the temperature frequently rises to such a degree as to give rise to inflammation of the liquid. Most of its salts are crystalline compounds but are very soluble and deliquescent.The composition of triethylphosphine" is represented by the formula El E Triethylphosphine forms crystalline compounds with the hydro- gen-acids of chlorine bromine and iodine with sulphuric and nitric acids; but all these salts which can be obtained in the dry state only by the aid of the exsiccator are but little suitable for analysis. The solution in hydrochloric acid affords a crystalline platinum-salt which is insoluble in cold water in alcohol and ether but which on account of the facility with which it decom-poses at 100' C. must be dried in the exsiccator. In the water- bath it fuses and is altogether decomposed. The determination of the platinum in the phosphorus-compounds presents considerable * The analytical details are giveu in the original paper published in the Philo- sophical Transactions for 1857,p.575. HOli’MANN AND CAXIOURS ON THE difficulties. The platinum in these substances cannot be deter- mined in the ordinary way by simple. ignition because a consider-able quantity of platinum is carried off with the phosphorus- vapour however slowly and carefully the process may be carried out. We unfortunately did not find this out until a great number of unsuc- cessful analyscs had been made. By heating with a considerable excess of carbonate of sodium in a porcelain crucible on a sand-bath the temperature of which is gradually raised the determina- tion succeeds without difficulty. After removal of the portion soluble in water the platinum-residue which is always contami- nated with silicic acid is dissolved in iiitrohydrochlloric acid the solution evaporated to dryness and- the residue again dissolved in acid thc careful evaporation of this solution furnishes a perfectly accurate result.This metliocl is somewhat tedious but there is some compensatiou for this iiicreased coniplexity by the simulta- neous determination of the chlorine. The analysis of the platinum-salt of tiaiethylphosphiiie has led to the formula Cl2HI5P HC1 PtCI,=E,P HC1 PtC1,. The analyses of the base itself and of the platinum-salt sufficiently fix the composition of triethylphosphine. This compound is in fact triethylamine in which the nitrogen is replaced by an equivs-lent quantity of phosphorus.The perfect analogy with triefhyla- mine is also shown by the deportment of the phospliorus-base with the iodides of ethyl methyl and amyl. Triethylphospliine com-bines with these substances forming well-crystallized and highly characteristic salts which may be regarded as iodide of amnio-nium in which the nitrogen is replaced by phosphorus and the hydrogen by the radicals of the alcohols. Iodide of TetretliyTp~~os~honiuln.-Onmixing triethylphosphine with iodide of ethyl a violent action ensues after a few moments; the liquid effervesces with almost explosive violence and then solidifies to a white crystalline mass. If instead of the pure base an ethereal solution be employed the crystals are formed more slowly. This new compound is extremely soluble in water less so in alcohol and insoluble in ether.The aqueous solution crystal- lizes on addition of potassa-solution in which this compound like the iodides of tetramethylammonium and tetrethylammonium is but slightly soluble. From the alcoholic solution the salt falls on addition of ether as a crystalline powder. If ether be added to a cold alcoholic solution as long as thc precipitate first produced is dissolved by boiling well-formed crystals of the iodide are deposited .on cooling. The mode of forination and the analysis leave no doubt respecting RESEABCHES ON THE PHOSPHORUS-BASES. the nature of these crystals. They contain the elements of 1 equiv. of triethylphosphine and 1 equiv. of iodide of ethyl. -C,,H,,P + C,H,I = C16H20PI.+ + Triethyl-Iodide of New compound. phosphine. ethyl. The new body corresponds to iodide of tetrethyl-ammonium. Notwithstanding the transparency of the constitution of these compounds we feel some embarrassment in fixing their nomen- clature. We propose to designate the hypothetical compound of one equivalent of phosphorus and four equivalents of ethyl by the name ‘‘Tetrethylphosphonium.” This term is long but it leaves no doubt regarding the composition of the body and marks at the same time its analogy with tetrethylammonium. The iodine- compound is accordingly the iodide of tetrethylphosphonium. Hydrated Oxide of Tetrethy~hosphonium.-The separation of the iodine from the before-mentioned compound presents no diffi-culties. Oxide of silver removes this element even at the common temperature.A strongly alkaline solution is obtained which retains a small quantity of silver in solution. This liquid which is almost without odour and has a bitter and phosphoric taste dries up when placed over sulphurjc acid into a crystalline, extremely deliquescent mass the silver separating at the same time in the form of a black powder or as a brilliant metallic mirror. The mass when redissolved in water furnishes a colour- less liquid free from silver but generally containing some carbonic acid. The avidity with which the oxide of tetrethylphosphonium attracts both water and carbonic acid has prevented us from ana- lysing this body but its formatian the composition of the corre- sponding iodide and the analyses of a platinum-and gold-salt hereafter to be mentioned sufficiently warrant the formula In its deportment with other substances the body in question resembles the oxide of tetrethylammonium ; we refer therefore to the detailed description which one of us has given of this com- pound in a former memoir.” The solution of the oxide of tetre-thylphosphonium shows in fact all the reactions of a solution of * Journal of the Chemical Society vol.4 p. 304. VOL. xr. F HOFMANN AND CAHOURS' potassa; the precipitates such as alumina and protoxide of zinc dissolve however less readily in excess of the phosphorus-compound. The action of heat upon this body gives rise to a peculiar transformation to which we shall return hereafter.Tetrethylphosphonium produces crystallizable salts with hydro- chloric nitric and sulphuric acids. All these compounds exhi bit the deliquescent character of the oxide. Like the latter they are also soluble in alcohol; in ether they are for the most part insoluble. The hydrochloric solution furnishes with bichloride of platinum and terchloride of gold difficultly soluble precipitates which are well adapted for analysis. Chloride of Tetrethy@hosphoniumund Bichloride of Plutinum-The pale orange-yellow precipitate which falls on addition of bichloride of platinum to a moderately dilate solution of the chloride dissolves with difficulty but without decomposition in boiling water; it is insoluble in alcohol and in ether. It can be dried at 100' C.Formula C16H2,PC1 PtCl =7PCl,PtCl,. E Chloride of TetrethyJphosphoniurn and Terchloride of Gold-The! arystalline precipitate obtained by mixing the two solutions sepa-mtes from boiling water in brilliant golden-yellow needles. ACTION OF HEAT UPON OXIDE OF TETRETHYLPHOSPHONIUM. The change which oxide of tetrethylammonium undergoes by the action of heat is well known ;this body splits into olefiant gas water and triethylnmine E,NO HO = C,H + 2H0 + E,N. We expected an analogous transformation of oxide of tetrethylphos-phonium but experiment has proved that this body suffers a different decomposition. On submitting freshly-prepared oxide of tetrethylphosphoniurn to distillation water only passes over in the first instance; but as soon as the solution has attained a certain state of concentration it suddenly effervesces with evolution of an inflammable gas which may be collected over water.This gas contains carbon and hydrogen but no phosphoms; it may be left RESEARCEES ON THE PEOBPHORUS-BABES. in contact with bromine-water without experiencing the slightest absorption. This experiment shows that the gas cannot contain any ethylene and with almost the same certainty we may infer the absence in it of all the hydrocarbons of the formula.C,H,. The evolution of gas ceases long before the whole amount of' the liquid contained in the retort has distilled over. On the contrary it is observed that immediately after the evolution of gas has ceased the distillation nearly stops and commences again only when the temperature has reached 200'; a viscid nearly inodorous liquid now distils over the temperature slowly rising until at about 240' a constant boiling-point is attained what now distils gene- rally solidifies to a radiated crystalline mass in the neck of the retort.On fusing this mass with a spirit-lamp and collecting the liquid in a receiver it frequently resolidifies instantaneonsly on cooling; often however it remains liquid for months. This body is extremely deliquescent a crystal exposed to the air only for a few seconds liquefies entirely. It is soluble in water in every pro-portion also in alcohol less so in ether. The aqueous solution is precipitated by potassa; the dissolved body separates in this case in colourless oily drops which remain liquid even after much con- centration and rapidly dissolve again on diluting the potassa solu-tion with a comparatively small quantity of water.Acids dissolve the oil likewise vith facility. It is obvious at a glance that the body in question is identical with the product formed by the action of air upon triethylphos- phine. A careful comparison of the properties of the two sub-stances places their ideutity beyond any doubt. It is moreover easily proved that the body is a product of oxidation. On boiling triethylphosphine with moderately strong nitric acid and adding potassa to the highly concentrated liquid the characteristic oily drops are immediately separated and disappear again upon addi- tion of water. At the common temperature oxide of mercury is without action upon triethylphosphine ;but on gently warming the mixture a considerable evolution of heat takes place metallic mer- cury is separated and an oily substance produced which has all the characters of the new compound and often sublimes in radiated crystals coating the colder part of the vessel.With oxide of silver exactly the same phenomena are observed. On the other hand the oily body when submitted to the action of potassium, instantaneously reproduces triethylphosphine. It is difficult to obtain this body in a state fit for analysis. It is not affected by solid hydrate of potassa but on distilling the two substances together the distillate is nevertheless found to contain a certain amount of moisture the hydrate of potassa losing a cer-tain quantity of water at the temperature of distillation.If the crystalline mass be separated from the potasss before distillation it attracts so much water during manipulation tliat even now it F% HOPMAINN AND CAHOURS’ becomes but irnparfcctly crystalline after distiliation. Distillation with anhydrous phosphoric acid ftirnishes the compound perfectly di-y and solid ; unfortunately however a portion of the substance is thus decomposed with separation of free phosphorus which con- taminates tlie distillate. Nor have we succeeded in uniting this substance to crystalline combinations ; nitrate of silver bichloride of platinum and several other reagents were tried in vain. It is obyious that the preparation of this body in a state of purity is attended with uniisual difficulties.These difficulties might cer- tainly have been surmounted but we believe that the deportment of triethylphosphine with sulphur and selenium which will be more minutely describ2d hereafter enables us to infer retrospectitely the composition of the oxide with a degree of certainty scarcely inferior to that furnished by analysis itself. The examination of well-defincd sulphur- and selenium- compounds of the composition xmwctive1.v “ Cl2FIl5PS2 =E,YS and C,,H,,PSe =E,PSe, sufficiently proves that the body in question is the corresponding oxide that it is in fact a combination of triethylphosphine with 2 equivalents of oxygen C,,€I,,PO,= 13,PO ; an inference which is moreover snpported by the existence of analogous and similarly formed combinations in the antimony- and arsenic-serics viz.C,,H,,SbO,=E,SbO, and C1,Hl5AsO2= E,As02. The formation of such a binoxide by the distillation of the hydrated oxide of tetrethylphosphonium is readily intelligible if we assume that the hydrocarbon simultaneously disengaged con- sists of hydride of ethyl an assumption which is in accordance with the general characters of this gas. E,PO HO = E,PO + EH Hydrated oxide of Binoxide of Hydride of tetrethylphosphonium. triethylphosphine. ethyl. We should have liked to establish this cquation by some analy- tical numbers but after some fruitless trials to prepare the sub-stance in a state of purity me were obliged to desist from the attempt.Even the preparation of a considerable quantity of oxide of tetrethylphosphonium is a long laborious and expensive opera- tion ; hut to these nunierous impediments a further difficulty is added which at tlie first glance appeared altogetlier inexplicable. Under certain conditions the distillation of oxide of tetrethylphos- phonium furnishes either no inflammable gas at all or only traces ; at the same time the formation of the crystalline binoxide either RESEARCHES ON THE PNOSPHOKUS-BASES. 69 entirely ceases or takes place only in very minute quantities. We have convinced ourselves that this invariably occurs when the alkaline solution by exposure to the air has attracted a consider- able quantity of carbonic acid.Instead of hydride of ethyl and binoxide of triethylphosphine the phosphorus-base itself is obtained in this case together with another liquid body which contains no phosphorus. By dissolving the distillate in ether fixing the triethylphosphine by sulphur and then evaporating tlie ether an inflammable aromatic liquid remains which floats on water. We had not more than a few drops of this oil at our disposal which prccluded the idea of an analysis but we have no doubt that this liquid is carbonate of ethyl. E,Y,CO = E,P + ECO,. Carbonate of Triethyl-Carbonatc tetrethylphosphonium. phosphine. of ethyl. Chloride Bromide and Iodide of Triet~~y~ho,~~~hine.-13inoxide of triethylphosphine when treated with hydrochloric hydrobromic and hydriodic acids is converted into the corresponding chloride bromide and iodide which closely resemble the oxide in their general properties.They are liquids which gradually solidify in the exsiccator; the crystals fuse at 100' and begin to volatilize although their boiling-point is very high. Thc compounds of triethylphosphine with chlorine bromine and iodine may also be obtained by the action of these elements in aqueous or alcoholic solutions upon the phosphorus-base itself. Both methods how- ever fnrnish proclucts which are difficult to purify. These compounds as well as the saline compoiinds which tlic oxide of triethylphosphine produces with sulphuric and nitric acids and which in the exsiccator gradually solidify into semi-crystalline masses have.but slightly occupied our attention because the for-mation of beautiful sulphur- and seleniuiri-compor~ndls enabled us to gain a sufficiently precise idea regarding the chemical characters of these substances in geiieral. Bisulphide of Tr..iethyl23hos~fzine.-Tlle Ten3arkable pheiiom ena which attend the combination of trietliylphospliine with sulphur have been already described. The compound is likewise olltained hy distilling triethylphosphine with cinnabar which in this reactiou ia reduced to subsulphide or to metallic mercury. Treatment of the oxide of triethylphosphine with sulpliuretted hydrogen or with sulpliide of amrnoiiium does not furnish the compound. The best mode of preparing this beautiful body is the following Illlowers of sulpliur are gradually introduced into a dilate solution of the phosphorus-base in ether ; the liquid efl'crvesccs iipn each addition and tlie sulphur disappears.As soon as sulphur remain- ing undissolved inr?icates the completion of the rcaction the ether 7S HOFMANN AND CAHOURS’ is volatilized and the residuary mixture of free sulphur and bisul- phide of triethylphosphine separated by boiling water. On cool- ing the liquid deposits the compound iu. crystals of perfect purity. This sulphur-compound is one of the finest products with which we have become acquainted in the course of our inquiries. Its crystal-lizing power is such that by slowly cooling the solution most beautiful crystals may be obtained even in a test-tube the liquid column being traversed by an aggregate of thin vertical needles of five or six inches in length.The difference of the solubility of the compound in cold and boiling water is very great; indeed but a minute quantity remains in solution at the common tempera- ture. On adding an alkali to the cold solution the mixture becomes turbid and deposits after a few moments small crystals. The sulphur-compound in this respect resembles the corresponding oxide which is likewise less soluble in alkalies than in pure water. This phenomenon is most strikingly observed by adding potassa to a boiling saturated aqueous solution of the bisulphide ; it instan- taneously separates in clear oily drops which rapidly solidify into spherical aggregates of crystals as the liquid cools.The compound is even more readily soluble in alcohol and ether and also crystal- lizes from these liquids but less beautifully. The solubility in bisulphide of carbon is almost unlimited; from this solvent it crystallizes imperfectly. The fusing-point of the bisulphide of triethylphosphine is 94O C. it resolidifies at 88’ C When heated beyond 100’ C. the bisulphide is volatilized with diffusion of a white vapour of a disagreeable sulphur-odour which is but slightly perceptible at the common temperature When heated with a quantity of water insufficient for its solution the sulphur-compound rises to tlie surface as a clear transparent oil which is copiously volatilized with the vapour of water. The solution of the bisulphide is without action on vegetable colours.The compound nevertheless appears to possess faintly basic properties. It dissolves more readily in hydrochloric acid especially when Concentrated than in water and the solution fur-nishes with bichloride of platinum a yellow precipitate which however rapidly cakes into a resinous mass giving indications of decomposition by the separation of bisulphide of platinum so that it was not adapted for analysis. The sulphur-compound also dis- solves in dilute sulphurio and nitric acids ; concentrated nitric acid decomposes it; the fuming acid gives rise to a sort of detonation. The aqueous solution of the bisulphide is not affected by acetate of lead nitrate of silver or protoxide of mercury even at the boiling temperature ; the alcoholic solution on the other hand is instan- taneouPly decomposed with separation of the sulphidc of lead silver or mercury.The liquid filtered off from the precipitates now contains the oxide of triethylphosphine eitber free or in tlie form of acetate REBEARCHES ON THE PHOSPHOBUS-BASES or nitrate and may be readily separated by the addition of an alkali to the solution. The action of potassium upon this compound in- stantaneously reproduces the phosphorus-base. The bisulphide of triethylphosphine has the composition C, H,,PS,=E PS,. The formation of the bisulphide takes place with such facility and the properties of the compound are so characteristic that we have frequently used flowers of sulphur as a reagent for triethyl-phosphine.BiseZenide of Triethylphosphine.-In the action of selenium upon triethylphosphine the phenomena described in the preceding para- graphs are repeated. The reaction however as might have been expected is less powerful. The selenium-compound crystallizes from water with the same facility as the sulphur-compound but the solution is apt to undergo partial decomposition when exposed to the atmosphere. Even the dry crystals are slowly reddened in the air. The fusing point of the selenide is llZo C.; it is easily volatilized undergoing partial decomposition. It contains C ,K ,PS e2=E,P Se2. In order to give more completely the history of the phosphorus-bases we have also examined the compounds which are formed by the action of the iodides of methyl and amyl upon triethylphosc phine; but since the products of these reactions resemble in every respect the corresponding ethyl-compounds we have only to men-tion the analytical results.Iodide of Methylt9.iethy~hos~honium.-In treating triethylphos- phine with iodide of methyl all the phenomenamentioned in the case of the analogous experiment with iodide of ethyl are repeated. The action is still more violent and rapid and if no ether be added a portion of the productIis readily lost by the explosive effervescence of the liquid The crystals thus obtained contain C14H18PI=(MeEJPI. On treating the solution of this compoiind which essentially resembles the simple ethyl-compound with oxide of silver a strongly alkaline solution of oxide of methyltriet h y lph osphoniurr is obtained.The solution when saturated with hydrochloric acid and mixed with bichloride of platinum furnishes a beautiful orange- yellow platinum -salt cry stallizing in well-defined cubes truncated by the planes of the octahedron. This salt which is insoluble in alcohol and ether may be recrystallized from boiling water without decomposition;it contains C,,H,,PCl PtC1,= (MeE,)PCl PtC1,. Iodide of TriethyZamylphosphonium.-Iodide of an@ acts but HOFMANN AND CAHOURS' slowly on the phosphorus-base. From a mixture of the two sub- stances in ether beautiful crystals are deposited after a few days which may be purified by solutionin alcohol and precipitation by ether ; they contain C,,HQ6PI = (E,Ayl)PI. Treatment of this compound with oxide 9f silver furnishes the free oxide of triethylamylphosphonium with all the properties cha- racteristic of the class.The corresponding chloride deposits on addition of biehloride of platinum a beautiful platinum-salt crys- tallizing in prisms with flat terminal planes. It is insoluble in alcohol and ether but rather soluble in water. The platinum-salt has the composition C,H,GPCI PtCI = (E,Ayl)PCl PtCl,. ACTlON OF HEAT UPON THE HYDRATED OXIDE OF TRIETHYLAMYL-PHOSPHONIUM. On heating this oxide a small quantity of an iiiflammable gas is evolved a liquid being formed at the same time which boils at about 283' C. and obviously corresponds to the binoxide of trie- thylphosphine. Two distinct changes may occur in this case.Since the oxide contains several radicals it is possible that either ethyl OF amyl may be eliminated in this decomposition and tho liquid simultaneously generated must therefore contain either (E,Ayl) PO, or E PO,. The higher boiling-point of the compound and the deportment of the corresponding nitrogen-term (the oxide of triethylamylarn-monium) which on distillation furnishes diethylamylamine toge-ther with water and olefiant gas are in favor of the first assump-tion. Accordingly the inflammable gas would also in this case be hydride of ethyl and the transformation of the oxide of triethyvl-amylphosphonium under the influence of heat wouid be represented by the equation (E,Ayl)PO HO = (E,Ayl)PO + EH- F Y l phosphonium. - Binoxide of diethyl-amylphosphine.Hgdrideof ethyl. Experimentally the question remains undecided. EXPERIIIENTS IN THE METHYL-SERTES. The results recorded in the preceding sections afford a tolerably complete view of the phosphorus-bases. We may therefore be brief ftESEARCHES ON THE PHOSPHORUS-EBSES. in describing the experiments which we have made with the methyl-compounds. TrimethyZ~hosphine.-This remarkable body is obtained by the same process which we have minutely described for the preparation of the corresponding ethyl-base. Zinc-methyl and terchloride of phosphorus furnish the compound of chloride of zinc and trirne- thylphosphine from which the base may be expelled by the action of' potassa. All the precautions wlzich have been mentioned as ne-cessary in the preparation of the ethyl-base are required in a higher degree for the methylated body.Since zinc-metliyl attracts oxy- gen even with greater avidity than zinc-ethyl the current of carbonic acid must be continuously maintained for a long period. The intensity with which zinc-metlig 1 decornposes terchloride of phosphorus is not inferior to the violerit reaction between caustic baryta arid anhydrous sulphuric acid. The mixing cam ot there-fore be too slowly effected. In expelling trimethylpliosyhine from its zinc-compound refrigeration by ice is absolutely necessary since this body is far more volatile than the ethyl-base. The distillation must be made in hydrogen gas and the current of gas must rnore- over flow very slowly otherwise however perfect and careful may be the arrangements for cooling a considerable quantity of the body will be carried off' in the hydrogen and be lost not to speak of the difk'usion of the almost intolerable odor of the methyl-base in the atmosphere of the laboratory.Trimethylphosphine is a colourless transparent very mobile liquid of an indescribable odour powerfully refracting light lighter than water in which menstruum it is insoluble. The boiling-point of the liquid lies between 40' and 42' C. which agrees with Paul Th 6n a rd's observations. Trimethylph osphine has even a more powerful attraction for oxygen than the corresponding ethyl-base. In contact with the air it fumcs and is apt to be inflamed. On distilling even the freshly prepared methyl-base the rreck of the retort becomes coated in the last stage of the operation with a net- work of beautiful crystals perfectly similar to those which are ob- served with the ethyl-base.These crystals may be readilr obtained in larger quantity by exposing the methyl-base to a slow current of dry atmospheric air. It is scarcely necessary to mention that these crystals are the Binoxide of trimethylphosphine. In its deportment with chlorine bromine iodine sulphur and selenium and finally .with the acids the methyl-base exzctly imitates the ethplated body. The reactions are however more rapid and energetic. We have been satisfied to identify trimethylphosphine prepared by means of zinc-methyl by the analysis of a platinum-salt. Hydrochlorate of Trimethyl]Jhosphine and Bichloride of Platinum.-The solution of the methyl-base in hydrochloric acid furnishes with bichloAe of pl:itiiium an orazlge yellow iiiclistinctly crystal- HOPMA” AND CAHOUR6’ line precipitate which like the corresponding ethyl-compound is readily decomposed by exposure to looo C. For analysis it waa dried in the exsiccator over sulphuric acid It contains C6H,P HC1 PtCI = Me,P HCl PtC1,. Iodide of Tetramet~y~ho~honium.-The iodide is a white crys- talline mass obtained by the action of iodide of‘ methyl upon an ethereal solution of triethylphosphine. This compound which may be readily recrystallized from alcohol is the finest product of the series. Freshly prepared it exhibits the silvery lustre of sublimed naphthalin.In contact with the atmosphere it assumes a slightly reddish colour. The composition of this compound is represented by the formula C,H,,PI = M,PI. On treating the solution of the iodide with oxide of silver a very caustic solution of the oxide is obtained. Chloride of Tetramethy~ohosphoniumand Bichloride of Platinum. -The solution of this oxide mixed with hydrochloric acid and bi- chloride of platinum furnishes a platinum-salt which is insoluble in alcohol and ether but crystallizes from water in beautiful octa- hedra. It contains C,H,,PCl PtC1 Me,PCl PtCl,. =3 Chloride of Tetramethy~hos~honium and Terchloride of Gold.-The method of preparation and the properties of the gold-salt of chloride of tetrnmethylphosphonium are perfectly similar to those of the corresponding ethyl-body.Formula CsH,,PCI AuCl = Me,PCl AuC1,. ACTION OF HEAT UPON THE HYDRrZTED OXIDE OF TETBAME-THYLPH0S 1°C) NT UM. Binoxide of Trimethy~hosphine.-Precisely similar phenomena as in the ethyl-series formation of binoxide of trimethylphosphine and hydride of methyl (marsh-gas). -ME,PO,HO = Me,HPO + MeH L-w L,-J Hydrated oxide of Binoxide of tri-Hydride of methyl tetramethylphosphonium. rnethylphosphine. (marsh gas) The direct formation of the binoxide by the action af oxygen upon trimethylphosphine has been already mentioned. Bisubhide and Biselenide of Trimethylphosphine.-These bodies likewise resemble the corresponding members of the ethyl-series ; they are however more soluble and more volatile.The sulphur- RESEARCHES ON THE PHOSPHORUS-BASES. compound crystallizes from a highly concentrated aqueous solution in masses of well-formed four-sided prisms which fuse at 105O C. The selenium-compound crystallizes exactly like the ethyl-body ; its fusing-point is 84OC. In contact with the air this compound blackens with separation of selenium. In this decomposition the characteristic odour of mesitilene is very perceptibly envolved. Even without an analysis me may assign to these compounds the formulz C,H,PS = Me,PS and C6H,PSe = Me,PSe,. In conclusion the action of the iodides of ethyl and my1 upon trimethylphosphine may be briefly mentioned. Iodide of Tri3nethylethylpho~phonium.-This substance is rapidly formed by the action of iodide of ethyl upon the ethereal solution of the methyl-base.The compound which crystallizes perfectly well from boiling alcohol contains C,,H,,PI = (Me,E)PX. Chloride of TrimethylethyIpho~phoni~cm and Bichhride of Plati-num.-By treating the iodide with oxide of silver the caustic oxide is obtained which gives with hydrochloric acid and bichloride of platinum a yellow platinum-salt insoluble in alcohol. and ether but rather soluble in water. From the boiling solutbn it is depo-sited in magnificent octahedra. Formula CloHl,PC1l PtCI = (Me,E)Cl PtCl Iodide of Trirnethylamylphospkonium.-The ethereal solution of tlie constituents slowly deposits this compound. It is extremely soluble in water and hence if the ethereal solution of the iodide of ethyl contain the most minute trace of water the salt separates in the form of a syrup which only gradually solidifies.It crystallizes in needles although with difficulty from absolute alcohol. Its composition is C16H,,PI = (Me,Ayl) PI. Chloride of Trimethylamylphosphonium and Bichlori tie of Plati-num. This oxide liberated from the iodide by means of oxide of silver furnishes with hydrochloric acid and bichloride of platinum a very soluble platinum-salt which crystalliEes from boiling water in splendid needles aggregated in spherules. Formula Cl6Hg0PC1 PtC1 = (Me,Ayl) PC1 PtC4. HOFMAIIN AND CANOURS’ The analysis of this platinum-salt concludes the experimental part of our inquiry ;for clearness and comparison we subjoin the following synapsis of the compounds wliich we have investigated.a. ME THYL-S E1% I ES. Trimethylphosphine ......Me,P. Platino-chloride of trimethylphosphine ..Me,P HC1 PtCI,. Binoxide of trimethylphosphine ... .Mt$?O,. Bisulphide of trimethylphosphine ...Me,PS,. Biselenide of trimethylphosphine . .Me,PSe,. Iodide of tetramethylphosphonium . ..MeiPI. Platino-chloride of tetramethylphosphonium .Me,PCl PtCl,. Auro-chloride of tetramethylphosphonium ..bfe4PCl AuC1 Iodide of trimethylethylphosphonium ..(Me,E)PI. Platino-chloride of trimethylethylphosphonium .(Me,E)PCl PtCl,. Iodide of trimethylamylphosphonium . ..(Me,Ayi)PI. Platino-chloride of trimethylamylphosphonium .(bIe3Ayl)PC1,PtCI-. p. ETHYL-SERIES. Triethylphosphine ......ESP.Platino-chloride of triethylphosphine ...E,P,RCl PtClP. Binoxide of triethylphosphine ....E,POp Bisulphide of triethylphosphine ....E,PS,. Biselenide of triethylphosphine . ..&PSe,. Iodide of tetrethylphosphonium ....EJPI. PIatino-chloride of tetrethylphosphonium . ,E4PG1 PtCI,. Auro-chloride of tetrethglphosphonium . .E4PC1 AliCI,. Iodide of methyltriethylphosphoninm ..(MeE3)PI. Platino-chloride of me thy ltriethylphosphonium ,(MeE3)PCl I’tCl? Iodide of triethylamylphosphonium ...(A71 E,)PI. Platino-chloride of triethylamylphosyhonium .(Ayl E3)PCI PtC1,. Oil glancing once more over the phosphorus-compounds described in the preceding memoir a comparison of these substances with the corresponding terms of the nitrogen- arsenic- and antimony- series is unavoidably forced upon us.Whether we consider the composition or whether me review the properties of these groups the most striking analogies indeed an almost perfect parallelism cannot be mistaken; the same forrniiliE the same mode of com-bination the same decompositions. This analogy is particularly manifest in the compounds helong- ing to the ammonium-type. In these remarkable bodies nitrogen phosphorus arsenic and antimony appear to play absolutely the same part. It is morc especially in the oxides of these compound metals that analogy of composition induces a perfect identity in properties arid indeed of very salietit properties which mzy be traced in almost every direction. If we were satisfied with tlie study of the reactions of these bodies we should never suspect in RESEARCHES ON THE PHOSPHORUS-BASES compounds exhibiting such a close similarity of properties the presence of elements so dissimilar as nitrogen phosphorus arsenic and antimony ; they might moreover be confounded VI ith potassa and soda by which they are scarcely surpassed in*alkaline power.Only the deportment of the hydrated oxides uu&r the influence of heat distinguishes the derivatives of nitrogen from the corre- sponding terms of the phosphorus- arsenic- and antimony-series. If we regard on the other hand the compounds belonging to the ammonia-type me observe that the electro-positive character of the substances gradually rises in intensity from the nitrogen- to the antimony-compounds.Thus trimethylamine and triethylamine are not capable of uniting with oxygen chlorine bromine and iodine ; a power which the corresponding terms of the phosphorus- arsenic- and anti- mony-series possess in a high degree. Triethylarnine unites with the acids producing cornpounds of the for mu1 it E,N HCl E,N HSO E,N HNO,. The corresponding compounds in the arsenic- and antimony-series do not exist ; at all events chemists have not yet succeeded in preparing them. Triethylarsine and triethylstibine only coin- bine directly with oxygen chlorine sulphur &c. pducing saline bodies which have the composition respectively -E,AsO . . . . E3Sb0 E,AsCl . . . . E3SbCl E,AsS . . . . E,SbS,. In the phosphorus-series lastly the two classes are repre-sented.Triethylpliosphine not only forms compounds analogous to the salts of triethylamine but also the terms corresponding to the binoxides of triethylarsine and triethylstibine MTe have in the first place the terms ESP,HCI E3P HSO E3P HNO, and in the second place compounds of the formulae E3PO2 E3PC1 E,PS,. The phosphorus-compounds accordingly hoid a position inter- mediate between the nitrogen-compounds on the one hand and RESEARCHES ON TEE PHOSPHORUB-BASES. the arsenic- and antimony-series on the other. It cannot howd ever be denied that the phosphorus-compounds stand closer to the arsenic- and antimony-series than to the nitrogen -group. This cannot surprise us when we consider the close analogies which phosphorhs and arsenic present in many other directions.Both phosphorus and arsenic form well-characterized polybasic acids; the acids of antimony are not yet sufficiently investigated but the acids of nitrogen which are better examined are all found to be essentially monobasic. The equivalent numbers too of phos-phorus arsenic and antimony present a remarkable connection the difference between those of phosphorus and arsenic and those of arsenic and antimony being virtually the same- Phosphorus . . . difference . . . 44, Arsenic . . . . . 75 "'2 . . . 45, Antimony . . . . 120J&difference whilst the equivalent of nitrogen stands altogether apart from the rest. The same relative position of the elements nitrogen phosphorus arsenic and antimony may also be traced in their hydrides H,N H3P H3As W,Sb.Ammonia is a powerful alkali ;-phosplzoretted hydrogen only unites with hydrobrornic and hydriodic acids whilst in arsenietted and antimonietted hydrogen the power of combining with acids has altogether disappeared. In these hydrogen-compounds the gradation of properties is indeed much more marked than in their trimethylated and triethylated derivatives. On comparing the terminal points of the series ammonia and antimonietted hydrogen we cannot fail to be struck by the dissimilarity of properties which at the first glance appears to limit the analogy of the two com- pounds to a mere parallelism of composition. In the methylated and ethylated derivatives of these compounds the intensity of the chemical tendencies in general is so much raised that the gradation is no longer perceptible to the same extent.We cannot conclude thisr memoir without thankfully acknow- ledging the able and untiring assistance we have received during this lengthened inquiry from Dr. A. Leibiua in the analyses and from Messrs. W. H. Perkin and C. Hoffmann in the prepara- tion of the numerous compounds which had to be investigated. On a New Series of 8rgani0 Aeids containing NWogen. By E. Frankland Ph.D. F.R.S. Lecturer on Chemistry at St. Barthelomew’s Hosyita€.* (Read before the Royal Society June 19 1866.) ABSTRACT. INthe progress made by Organic Chemistry during the past fifteen years no generalization has perhaps contributed so extensively to the development of this branch of the science as the doctrine of substitution.The value of this doctrine becomes even still more apparent when it is remembered that chemists have until very recently possessed adequate means for following out its sugges-tions in one direction only. The peculiar habits of chlorine render the substitution of an electro-positive constituent by this element generally a work of little or no difficulty and even the like substitution of other electro-negative for electro-positive elements in organic bodies presents no insurmountable obstacles. But the inverse process has hitherto been successfully accomd plished only in comparatively few cases owing to the want of a body capable like chlorine of effecting such a replacement with facility.This want is now supplied in zincmethyl and its homo- lopes; bodies which on account of their intense affinities and peculiar behaviour possess in an eminent degree the property of removing electro-negative constituents and replacing them by methyl ethyl &c. The action of zincmethyl upon water attended as it is by the substitution of methyl for oxygen C H Zn C,H,,H %o)={zno may be regarded as the type of these reactions which open up a most extensive and perfectly new field of research from the culti- vation of which important discoveries cannot fail to spring. Amongst the reactions of this nature which promise most interest- ing results are those with the chlorine and oxygen substitution products derived from the ethers and organic acids which might lead to the higher members of each homologous series being pro- duced from the lower ones if not to the building up of some of those series from their inorganic types ; a discovery which cannot now remain long in abeyance.? Instead of immediately pursuing this line of investigation however I determined in the first place to confine my attention to the action of these organo-zinc bodies upon inorganic compounds.In a former memoir$ I endeavoured to give a general view of * Phil. Trans. 1857 59. t This discovery has since been made by Mr. WankIyn who haa succeeded in forming propionic acid from carbonic acid by the action of Bodium-ethyl upon the latter body.-April 1858. E. F.$ Phil. TI~M.,1852 438. FRANKLAND ON A NEW SERIES OF the rational constitution of all the organo-metallic bodies then known by showing that they all possessed a molecular isonomy with the inorganic compounds of the respective metals. The only compoucd which at that time did not coincide with this Y'iew was LSw I G' s so-called ethostibylic acid the formula of which SbC,H,Q, I suggested would probably be found to be erroneous*; and in fact LOWIGhas since announced this to be the case he now assigns to this compound the formula Sb(C,H,),O, ZSbO, which harmonizes perfectly with the general view I ventured to propound. The recent researches of 3%E RC Kt upon the compounds of atibe-thyl although they probably prove the existence of certain new compounds of this radical are by no means conclusive as to the non existence of the bodies originally described by L iiw I G.With regard to those stanethyl compounds which haire been since dis- covered several of them corrcspond exactly with the known oxides of tin; the remainder are also by no means irreconcileable with my hypothesis if we consider the polymeric attributes of stannic acid. Nevertheless I conceive that the formulze and even the existence of some of the more complex stanethyl compounds require con-firmation before these bodies can be employed either for the support or disproof of any general theory of the rational constitu- tion of organo-metallic compounds. Taking then this view of the organo-metallic compounds as my guide I pointed out in a former memoir,$ that the oxygen com-pounds of nitrogen might probably be represented by correspond-ing organic compounds in which one or more equivalents of oxygen were replaced by an organic radical thus to take one example nitric acid by the substitution of methyl should yield the following derivatives :-I.11. 111. IV. V. of which the fourth is already known as oxide of tetramethylam- monium. My attempts to produce these derivatives from the oxygen compounds of nitrogen have hitherto been confined to the binoxide in which I have succeeded in replacing oxygen by ethyl in the manner now to be described. Action of Zincethyl upon Binoxide of Nitrogen. If a small quantity of zincethyl either pure or dissolved in ether be passed up into dry binoxide of nitrogen confined over * Phil.Trans. 1852 442. -t. J. pr. Chem. lxvi 56. S Phil. Trans. cxliii ;442. ACIDS CONTAINING NITROGEN. 81 mercury the binoxide is very slowly but completely absorbed in large quantity without the production of any other gas. The solution may be accelerated by agitation but even then it is exceedingly slow. At the expiration of from one to four clays rhomboidal crystals begin to be deposited and increase in number until the liquid finally solidities. To prepare these crystals in larger quantity about an ounce of zincethyl dissolved in an equal bulk of dry ether was placed in a flat-bottomed flask and supplied with binoxide of nitrogen from a gas holder the gas being thoroughly dried by bubbling through a long series of bulbs filled with concentrated sulphuric acid which also servcd to absorb any traces of nitrous gas that might be formed by atmospheric oxygen gaining access to the interior of the appzratus.The gas was con-ducted into the flask by a tube which terminated just below the cork; whilst a provision was made for its exit by another tube continued to within a short distance of the surfacc of the liquid and which terminated outside the cork in a capillary extremity that could be readily sealed up by the blowpipe mid reopelied at pleasure. Binoxide of nitrogen prepared from copper turnings and nitric acid always contains a considerable percentage of protoxide and it was therefore necessary occasiorially to allow a stream of the gas to flow through the flask so as to prevent the absorption being hindered or stopped by the accumulation of protoxide of nitrogen at other times the exit tube was lierinetically sealed and the gas supplied only as it was absorbed.In this way although the apparatus was in action day and night six weeks elapsed before tlie absorption was completed. Oil another occasion when the action mas accelerated by violent agitation of the liquid for sevcral hours each day the ziiicethyl was saturated in about a fortnight. It was evident that such a process mas little calcula-tcd for the production of considerable quantities of tlic new compound and recourse was therefore had to mechanical means in order to expedite and facilitate the operation. Fig.1is from a photograph of the apparatus employed for this purpose and as it will no doubt prove useful iii other cases for experiments with sparingly soluble gases I will describe it somewliat in detail. A is a copper digester similar to the one 1 have already described for the preparation of zincethyl*; into tlie aperture b is screwed the stopcock c to which can be attached at pleasure the con- densing syringe D made of gun-metal 12 inches long and 0.7 inch in diameter. In this syringe a solid steel piston 12 inch deep works air-tight and the piston-rod passes through a stuffing- box f. The syringe is supplied with gas through the nozzle e to which a flexible tube is attached. When the stopcock c is * Phil. Trans. cxlv 261. G FRANKLAND ON A NEW SERIES OF closed the elevation of the piston produces a vacuum which is instantly filled with gas so soon as the piston has passed the nozzle e.Between e andf the interior of the syringe is grooved loiigitudinally so as to prevent any compression of gas behind the piston when it is drawn up tot. On forcing down the piston and opening the stopcock c it is obvious that the gas occupying the syringe from e to c will be forced into A. By repeating this process it is not difficult for a single operator to compress about twenty atmospheres into A; such a degree of compres-sion exerting upon the piston a pressure of about 114lbs. In each operation about three ounces of zincethyl in ethereal solution was placed in the copper cylinder A and the condensing syringe being attached about twenty atmo- spheres of dry binoxide of uitrogen were introduced; the syringe was unscrewed and the the cylinder A agitated for two or three minutes by rolling upon the floor or otherwise; at the end of which operation the pressure within A was found to be reduced to three or four atmospheres; the process of condensation and agitation being repeated five or six times the copper cylinder becomes so much heated as to require immersion in cold water for a few minutes.At this stage of the process it is also desirable to allow the residual gas in A to escape. This residual gas consists principally of protoxide of nitrogen and hydride of ethyl; the latter derived from the decomposition of zincethyl by a trace of aqueous vapour introduced with the binoxide of nitrogen.By repeating the above series of operations six or eight times the zincethyl becomes saturated and the process is completed. If it be desired to obtain the crystalline compound in a state of perfect puritg it is better to place the zincethylin a wide glass tube open at top and fitting into A ;but in this case very moderate agitation only can be used and consequently the absorp- tion takes place more slowly and the operation requires two or ACIDS CONTAINING NITROGEN. three days for its completion. It is however rarely necessary to have recourse to this modification of the process. At the conclusion of an operation conducted as above with the intervention of a glass tube the contents of the latter consisted of a mass of colourless crystals immersed in an ethereal solution; the latter was poured off and the former were freed from ether by plunging the tube in a water-bath at 90' C.and passing through it a stream of dry carbonic acid. The resulting crystalline mass attracted oxygen from the air with such avidity as to burst into flame when any considerable quantity was freely exposed; it was also instantly decomposed by water and was therefore transferred at once into small glass tubes which were then immediately sealed hermetically. The results of the analtlyscs prove that the new body is formed by the union of an equal number of atoms of zincethyl and binoxide of nitrogen; hut from considerations given below the above formula requires to be doubled and I shall presently shorn that the body is a compound of zincethyl with the zinc salt of a new acid for which I propose the name Diizitroethglic acid Its formula is therefore N,C,H,O,Zn + ZnC,H,.This compound is produced from zincethyl and binoxide of nitrogen according to the following equation :-2'g2y5)} =N,C,H50,Zn + ZnC,H,. Dinitroethylate of zinc and zincethyl is deposited from its ethereal solution in large colourless and transparent rhomboidal crystals which instantly become opaque on exposure to the air owing to the formation of an oxidized product These crystals are tolerably soluble in anhydrous ether without decomposition but they are instantly decomposed by anhydrous alcohol and by water.Exposed to the gradually increasing heat of an oil-bath dinitroethylate of zinc and zincethyl fuses at lOO'C. froths up and begins slowly to evolve gas. At 180' C. the colour darkens and a small quantity of a yellowish liquid of a penetrating odour free from zincethyl and possessing a very powerful alkaline reaction distils over. This liquid neutralized with hydrochloric acid and treated with bichloride of platinum yielded a splendidly crystalline platinum salt which was obtained however in too small quantity to allow of its composition being determined. From 180' to 1909C. dinitroethylate of zinc and zincethyl evolved gas very rapidly and the experiment was then interrupted. The gas consisted of 18.4 per cent.carbonic acid 23.66 per cent. olefiant gas and 57-94per cent. of a mixture of liydride of ethyl nitrogen and protoxide of nitrogen. 62 PRANKLANO ON A NEW SERIES OF When brought into contact with water dinitroethylate of zinc and zincethyl is immediately decomposed with lively effer-vescence. A large quantity of inflammable gas is evolved and a white flocculent substance formed. At the conclusion of the reaction the latter dissolves almost completely forming an opalescent solution resembling milk possessing a powerfully alkaline reaction and a peculiarly bitter taste. In order to ascertain the exact nature of the gas evolved in this reaction some crystals of dinitroethylate of zinc and zincethyl were passed up into an inverted receiver filled with mercixry and were then brought into contact with a small quantity of water.The gas thus collected over mercury possessed an ethereal odour burnt with a slightly luminous flame and was completely soluble in an equal volume of alcoliol. It as perfectly neutral and underwent no change on being treated successively with caustic potash solution and dilute sulphuric acid. The specific gravity of the gas was found to be 1.0515 whicli together with the results of its eudiometrical anaiysis show it to be pure hydride ofethyl. On submitting the milky solution formed by the decomposition of dinitroethylate of zinc and zincethyl in water to a stream of carbonic acid a copious precipitate of carbonate of zinc free from organic matter was thrown dowri the liquid was then heated to boiling and filtered.The filtrate cvapoxated almost to dryness in a water-bath yielded a white radiated crystalline mass which after being reduced to powder pressed between blotting-paper and dried over sulphuric acid was submitted to analysis the results of which correspond with the formula Z(N,C,H,O,Zn) +NO. The composition of this body proves that the action of water upon dinitroethylate of zinc and zincethyl consists in the trans- formation of the zincethyl into oxide of zinc and hydride of ethyl thus The neutr.d dinitroe thylate of ziiic howevc;. thus set at liberty immediately unites nith a second cquivaleiit of oxide of zinc to form the basic salt N2C,H,0,Zn +ZnO whicli is decoinposed by carbonic acid into carbonate of zinc and the neutral salt.Dinitroethylate of zinc crystallizes with half an equivalent of water which is expelled at 100° C. the loss in drying being 3-98 per cent. and 3.75 per cent. respectively whilst the theoretical number is 3.57. Dinitroethylate of zinc is also produced by the direct oxidation ACIDS CONTAINING NITROGEN. of dinitroethylate of zinc and zincethyl in a stream of dry air ethylate of zinc being at the same time formcd the completion of' the oxidation is known by the product ceasing to effervesce in contact with water. This reaction is expressed by the following equation :-N2C,H,0,Zn +C,H6Zn >={N,C,H60,Zn ZnO,C,H,O. 02 When this prodi;ct is treated with water alcohol and bibasic dinitroethylate of zinc are produced N,C,H,O,Zn N,C,H,O,Zn +ZnO HO C,H,O,HO.One of the equivalents of base being removed by carbonic acid the filtered solution of the neutral salt thus obtained was evapo-rated to crystallization and the crystzls heated to 100' for some time; at this temperature they fused and afterwards solidified in cooling to a gummy mass which analysis proved to be the nnhy- drous dinitroethylate of zinc. Finally dinitroethylate of zinc and zincethyl is produced by adding an ethereal solution of zincethyl to anhpdrous dinitroethy- late of zinc and corresponding compounds appear to be formcd under similar circumstances with other salts of dinitroethylic acid. These compounds are evidently of the same nature as that pro- diiced by the union of zincethyl with iodide of zinc which is formed in such large quantity during the preparation of zincethyl.Dinitroethylate of zinc crystallizes in minute colourless ncedles containing half an equivalent of water ~hich they retain \\-hen exposed over sulphuric acid in vacuo. Tlicy fuse below 100' C. and gradually become anhydrous at this temperature. They are very soluble in watcr and in alcohol. The concentrated aqueous solution solidifies on cooling to it white fibrous crystalline mass. Heated suddenly in air to a temperature of about 300° this salt does not deflagrate but it inflames burning rapidly with a beautiful bluish-green flame. When dry dinit+oethylate of zinc is treated with concentrated sulphuric acid and the vessel containing those ingredients is placed in a freezing mixture dinitroethylic acid is liberated; but it is so unsiablc that when the temperature rises a few degrees it begins to effervesce violently and is rapidly decomposed with evolution of gases and white vaponrs.A dilute solution is somewhat more stable ;it may be prepared either by decomposing a dilute solution of dinitroethylate of zinc with dilute sulphuric acid and then distilling in vaczto or by adding to a dilute solution of the baryta salt just sufficient sulphuric acid to precipitate the base. Dilute dinitroethplic acid thns prepared possesses a punpit odour soiiiewliat i.csemtling that of the nitro- FRANKLAND ON A NEW 8ERIES OF fatty acids and an acid taste. It reddens litmus-paper strongly and gradually decomposes even at ordinary temperatures.The acid procured by distillation in wacuo being treated with carbonate of silver the latter dissolved with evolution of carbonic acid. The filtered solution evaporated over sulphuric acid depo- sited light flocculent crystals of dinitroethylate of silver which blackened rapidly. They gave by treatment with nitric acid and subsequent ignition 55.85 per cent. of metallic silver. The formula N,C,H,O,Ag requires 54-82 per cent. Another por-tion of the dilute acid procured by the decomposition of the baryta-salt as described above was saturated with magnesia evaporated to dryness and the residue treated with strong alcohol. Tlie filtered alcoholic solution which contained no trace of sul-phuric acid gave on evaporation dinitrocthylate of magnesia which by treatment with nitric acid and ignition yielded 19.64 pcr cent.of magnesia. The formula N,C,H,O,Mg requires 19.80 per cent. The salts of dinitroethylic acid are all soluble in water and alcohol and most of them crystallize with more or less diaculty. They ere all violently acted upon by concentrated nitric acid the dinitroethylic acid being entirely decomposed and a nitrate of the constituent base produced. Dilute nitric acid acts in the same manner but more slowly. They all fuse at a temperature a little above 100' C. The potash sod%,lime and baryta-salts deflagrate explosively like loose gunpowder at a temperature considerably below redness. Dinitroethylute of Baryta.-N,C,H,O,Ba.This salt is pro-duced by adding caustic baryta in excess to a solution of dini-troethylate of zinc carbonic acid heing passed through the solu- tion until the excess of baryta is precipitated. It is then treated with sulphuretted hydrogen to remove a tracc of oxide of' zinc which is still held in solution. After being heated to boiling for n few minutes and then filtered the solution is concentrated by evaporation and finally dried down to a gummy mass which does not crystallize on cooling. This is anhydrous dinitroethylate of baryta. Dinitroethylate of baryta is uhcrystakable very deliquescent and very soluble in water. Its solution reacts perfectly neutral. Dinitroethylic Ether.-Several attempts were made to prepare this compound by the usual methods of etherification but with only very partial success.When crystallized dinitroethylate of lime is distilled with sulphovinate of potash alcohol comes over mixed with an ethereal liquid which dissolves in water but sepa-rates again on the addition of chloride of calcium in the form of oily drops of a peculiar ethereal odour. I only succeeded however in obtaining such minute quantities of this body as to preclude the possibility of fixing its composition. ACIDS CONTAINING NITROGEN. Dinitroethylate of Lime.-N,C,H,O,Ca +3H0. This salt is readily prepared by treating solution of dinitroethylate of zinc with excess of hydrate of lime passing carbonic acid through the solu- tion and then heating to boiling for a few minutes.The filtered solution deposits on evaporation beautiful silky needles of dini-troethylate of lime which contain three atonis of water two of which are expelled at 100' C. An estimation of lime in this salt gave 20.76per cent. ;the above formula requires 20.59 per cent. Dinitroethylute of Silver is produced by double decomposition from dinitroethylate of baryta and sulphate of silver. It is very soluble in water crystallizes in very light scales and is so speedily decomposed even with little exposure to light that no satisfactory analysis could be made. Double Nitrate and Dinitroethylute of Silver. -AgONO -+ AgON,C,H,O,. This salt is very sparingly soluble in water ; it is precipitated in a crystalline granular form when concentrated solutions of dinitroethylate of zinc and nitrate of silver are mixed.Dinitroethylute of Copper.-2 (N,C4H5Cu0,) + HO. This salt is prepared by mixing solutions of dinitroethylate of baryta and sulphate of copper. The filtered solution is of a magnificent purple colour ; on evaporation in vacuo it yields splendid purple needles which contain half an equivalent of water and may be obtained several inches in length ;they are four-sided prisms. Dinitroethylate of Magnesia N,C,H,MgO,. -Prepared by treating the solution of dinitroethylate of zinc with excess of caustic magnesia boiling and filtering. The filtered solution con- centrated in a water-bath yielded granular crystals which fuse at 100OC. and dry up to a solid amorphous mass. This is the anhydrous salt.DinitrGethylate of Soda N,C+H,O,Na.-Prepared by precipi- tating dinitroethylate of lime with carbonate of soda and evapo- rating the filtrate in a water-bath. The residue being treated with strong alcohol the dinitroethylate of soda dissolves and is thus separated from the excess of carbonate of soda. The alcoholic solution evaporated to dryness iri a water-bath yielded minute scaly crystals which were anhydrous. Products of the Decomposition of Dinitroethylic Acid. I have stated that when dinitroethylic acid is liberated from its salts by the addition of concentrated sulphuric acid it is rapidly decomposed even at 0' C. I have examined the products of this decomposition in the case of the lime-salt with the following results. A quantity of crystals of dinitroethylate of lime in coarse powder was placed in an apparatus in which it could be gradually decomposed by concentrated sulphuric acid the gaseous products collected and their weight accurately ascertained.The rapidity FRANKLAND ON A NEW SERIES OF of decomposition was moderated by the external application of cold water. At the conclusion of the decomposition it was found that the weight of the gaseous products evolved was equal to 30.6 per cent. of the meight of the lime-salt employed. The weight of gaseous products is therefore almost exactly one-half of the weight of the anhydrous acid contained in the lime-salt (59.6 per cent .) . The liquid and solid products of the operation contained sulphate of lime sulphovinate of lime and sulphate of ammonia or ethylamine.These gaseous products after streaming through concentrated sulphuric acid mere collectcd over mercury and sub-mitted to eudiornetrical investigation. The specific gravity was found to be 1.3601. The mean percentage composition of the gas was Binoxide of nitrogen . . 8.90 Olefiant gas . . 24-24 Protoside of nitrogcn . . 60.65 Nitrogen . 6-21 100.0 This result is confirmed by the specific gravity of the gas as is seen from the following calculations :-Per cent. Specific amount. gravity. Binoxide of nitrogen . . . 8.90 x 1*0365= 9.2249 Protoxide of nitrogen . . 60.65 x 15202= 92.2001 .- Olefiant gas . .. .. -. 2::ii}x *96'74= 294573 Nitrogen -130.8823 100*00 --1.3088 100 Foundbyexperiment .. . . . . . 1.3601 1:had anticipated that the decomposition of dinitroethylate of lime by sulphuric acid would yield either protoethlde of nitrogen (NC,HS) or ethoprotosidc of nitrogen (NC,H,O) but the action of the concentrated acid evidently proceeds too far for the produc- tion of this result. Further experiments must decide whether or not the cmployment of a more dilute acid for the decomposition mill lead to the production of onc of these compounds. Action of Zincmethyl upon Rinoaide cf Nitrogen Dinitromethylate of Zinc and Zincmethyl.-Zincmethyl absorbs binoside of nitrogen much more slowly than zincethyl takes up the same gas ;nevertheless at the ordinary atmospheric pressure the two bodies padually unite and form colourless crystalline needles closely resembling in all their reactions the dinitroethylate of zinc and zincethyl.I have made no analyses of this body but ACIDS CONTAINING NITROGEN. considering the homology existing between zincethyl and xinc- methyl together with the product of its decomposition by water there can scarcely be a doubt that it is dinitromethylate of zinc and zincmethyl and that its formula is N,C,H,O,Zn +C,H,Zn. It rapidly oxidizes in the air and takes fire when exposed in considerable quantity. It is instantly decomposed by water giving light carburetted hydrogen and an opalescent solution of basic dinitromethylate of zinc. Dinilromethylute of Zinc N,C,H,O,Zn +H0.-A quantity of the dinitromethylate of zinc and zincmethyl mas prepared by the action of compressed binoxide of nitrogen upon zincmethyl in the strong copper vessel above described.The resulting crystalline compound was decomposed by water and the opalescent solution being treated with carbonic acid boiled and filtered yielded on evaporation minute crystals of dinitromethylate of zinc. Dinilronaethykute of Soda N2C2H,0,Na +2HO.-This salt is formed by treating a solution of dinitromethylate of zinc with car-bonate of soda evaporating to dryness and treating the residue with strong alcohol. Dinitromethylate of soda dissolves and the filtered solution on evaporation deposits crystals which after drying at 10QoC. yielded 25.83 per cent. of soda; the above formula requires 26.72 per cent. Dinitromethylate of soda is very soluble both in water and alcohol ;it ileflagratx violently when heated and in other rcspccts closely resembles the cor-responding salt of dini troethylic acid.These determinations although very imperfect and incomplete establish the existence of a class of salts containing dinitromethylic acid homologous with the dinitroethylates; and there can be little doubt that the zinc compounds of the other alcohol-radicals will yield corresponding acids when treated with binoxide of nitrogen. It is difficult to form any satisfactory hypothesis relative to the rational constitution of this series of acids they may be regarded as belonging to the type of nitrous acid containing a double atom of nitrogen and in which one atom of oxygen has been replaced by an alcohol radical thus- or they may be viewed as constructed upon the hyponitrous acid F.WGHLER AND H. BUFF type one equivalent of oxygen being replaced by an alcohol radical and a second atom by binoxide of nitrogen thus- Without attaching much value to either hypothesis I prefer the latter. By analogous processes there can be little doubt that many new series of organic acids may he derived from inorganic acids by the replacement of one or more atoms of oxygen by an alcohol-radical; in fact my pupil Mr. HOBSON now studying a new series con-is taining sulphur produced by the action of zincethyl and its homologues upon sulphurous acid the ethyl acid of this series is formed by the replacement of one equivalent of oxygen in three equivalents of sulphurous acid by an alcohol-radical.The following Table exhibits the compounds of the new series of acids which have been described in the foregoing pages Formule. DinitroethyIic acid . . . . . N,C,H,O,H. Dinitroethylate of silver. . . . . N,C4H,0,Ag. Dinitroethylate of copper . . . 2(N2C,H,04Cu) +HO. Dinitroethylate of zinc (crystallized) . 2(N,C,H,O,Zn) -t HO. Dinitroethylate of zinc (anhydrous) . . N2C,H,04Zn. Dinitroethylate of baryta . . . . N,C,H,O,Ba. Dinitroethylate of lime . . . . . N,C,H,O,Ca+ 3H0. Dinitroethylate of magnesia . . . N$,H,O,Mg. Dinitroethylate of soda . . . N,C,H,O,Na. Double nitrate and dinitroethylate of silver . NO,Ag + N,C,H,O,Ag. DinitroethyIate of zinc and zincethyl . . N,C,B,O,Zn +C,H,Zn.Dinitromethylic acid . . . . N,C,H,O,H. Dinitromethylate of zinc . . N,C,H,O,Zn +Ho. Dinitromethylate of soda . . N,C,H,O,Na t 2H0. Dinitromethylate of zinc and zincmethyl N2C2H,0,Zn t C2H,Zn. On some new Compounds of Silicon,* BY F. WOHLERAND H. BUFF. Siliciuretted Hydrogen.-A gaseous compound of silicon and hydrogen is produced when a bar of aluminium containing silicon is connected with the positive pole of a Bunsen’s battery of 8 to 12cells and made to dip into a solution of chloride of sodium. The aluminium then dissolves in the form of chloride a consider-* Ann. Pharm. ciii 218 ;civ 94. ON SOME NEW COMPOUNDS OF SILICON. able quantity of gas is evolved at its surface and many of the gas-bubbles as they escape into the air take fire spontaneously burning with a white light and diffusing a white fume.When the gas is collected in a tube over water and bubbles of oxygen passed up into it each successive bubble produces at first a brilliant white light and a copious white fume; but this effect gradually diminishes in intensity and at last the remaining gas mill no longer burn spontaneously by contact with oxygen. This residual gas is hydrogen ; the spontaneously inflammable gas which forms but a small portion of the mixture is siliciuretted hydrogen. When the gaseous mixture is made to escape from a glass jar provided with a stop-cock it burns in a jet and deposits silica round the orifice. A piece of white porcelain held in the flame becomes stained with a brown deposit of silicon; and if the gas be made to pass through a narrow glass tube and heated till the glass softens a deposit of silicon is likewise obtained and the gas which issues from the tube is no longer spontaneously inflam- mable.The compound has not yet bcen analysed quantitatively. The formation of siliciuretted hydrogen appears to be due to a secondary action accompanying the electrolysis of the saline solution. The aluminium forming the positive pole of the battery combines with the chlorine and dissolves; but the quantity of aluminium removed is about one-fourth greater than that which is equivalent to the quantity of chlorine eliminated from the solution. This excess of aluminium is found to be removed in the form of alumina uniting with oxygen derived from the water of the solution.The equivalent quantity of hydrogen is of course evolved and part of it enters into combination with the silicon contained in the aluminium. The compound has not yet been obtained by a purely chemical reaction; but it has been observed that the hydrogen evolved when aluminium dissolver in hydro- chloric acid burns with a brighter flame than pure hydrogen and yields a small deposit of silica. Chloride of Silicon and Hydrogen. Si,Cl, 2HCl.-This com-pound is obtaincd by heating crystalline silicon to a temperature somewhat below redness in a stream of hydrochloric acid gas. The silicon in fine powder is disposed throughout the entire length of a long glass tube one end of which is connected with an apparatus for evolving dry hydrochloric acid gas while to the other is attached a long-legged U-tube cooled by a mixture of ice and salt and fitted with an escape tube having its aperture widened like a funnel and dipping into a large vessel of ice-cold water.As soon as the apparatus ia filled with hydrochloric acid gas the tube is surrounded with hot coals and heated to a temperature short of visible redness; at a higher temperature the ordinary terchloride of silicon would be formed. The hydrochloric acid is F. WOHLER AND H. BUFF then decomposed; bubbles of inflammable hydrogen gas pass through the water and at the same time a white substance which is a new oxide of silicon is separated being produced by the action of the water on a portion of the ctiloride of silicon and hydrogen which is carried forward with the stream of hydrogen.At the end of the operation the U-tube is found to contain a turbid liquid which is the chloride of silicon and -hydrogen mixed with other compounds. When subjected to fractioiinl distillation it begins to boil at about 28' or 30' C the temperature hawever quickly rising to between $0' arid 43' between which limits the largest portion of the product which is the chloride of silicon and hydrogen passes over. The temperature ultimately rises to 60° and on one occasion it rose to 92O. Chloride of silicon and hydrogen is a colourless very mobile liquid which has a very pungent odour fumes strongly in the air and covers everything aroiind it with a white film.Its boiling point is about 42'; spccific grabity 1.65. It docs not conduct electricity. Its vapour is as inflammable as ether-rapour and burns with a faintly luminous greenish flame difl'using vapours of silica and hydrochloric acid. When a Cew drops of the liqiiid are passed up into oxygen gas in an eudiometer tube over merciiry and left to evaporate a gaseous niivture is formed which explodes violently when an electric spark is passe6 through it producing a whits flame and covering the inner surface of the tube wit11 a white film of silicic acid. The residual gas consists of hydrochloric acid and terchloride of silicon the compound having given up half its silicon to form silicic acid. The vapoiir passed through a imrrow red-hot tube is quickly decomposed into amorphous silicon which coats the inside of the tube with a brown specular deposit and a mixture of hydrochloric acid and terchloride of silicon.Herice thc necessity of keeping the heat below redness during the preparation. When the vppour is passed over aluminium in the state of fusion it is very easily decomposed hydrogen being set free chloride of aluminium subliming and the reinainder of the aluminium becoming covered with a loose crust of crystallized silicon. The tube is at the same time coated internally with amorphous silicon in consequence of part of the compound being decomposed merely by the heat in the manner above described. In contact 1~6th matcr the compound is instantly decomposecl with great rise of temperature yielding hydrochloric acid and hydrated sesquioxide of silicon (1'.93). If a smali dish full of the liquid chloridc be placed over a surface of watcr and the n-liolc covered with a bell-jar the liquid quickly disappears aiid the surface of the water becomes covered with a thick crust of the oxide. The rapour of the chloride is rapidly absorbed by alcolicjl and ON SOME NEW COMPOUPU'DS OF SILICON. ether without separation of oxide. The solutions fume in the air and when left to evaporate over sulpliuric acid and hydrate of lime they leave a partly earthy partly translucent oxide which appears to coiitain an ethyl-compound (silicic ether 3). The alcoholic solution solidifies after a while into a translucent jelly. The preceding reactions sufficiently indicate the composition of the new chloride which is further confirmed by the analysis giving as a mean result 3 9-14 p.c. silicon and 80.913p. c. chlorine while the formula Si,Cl, 2WC1 requires 19.18 Si and 79-92 C1. Bromide of Silicon and Hydrogen. Si,Br, 2HBr.-Prepared like the chloride. It is at first coloured yellow by free bromine but may be decolorised by means of' mercury. It is a colourless liquid which fumes very strongly in the air. Its specific gravity is approximately 2.5. When immersed in water it is decomposed like the chloride but immediately becomes covered with a coat of oxide which for a while protects it from further decomposition. Iodide of Silicon and Hydrogen. Si213. 2HI.-Prepared like the chloride and bromide excepting that there is no necessity for a receiver inasmuch as the iodide being less volatile and solid at ordinary temperatures condenses at the cool end of the tube in which the decompositioii takes place.It forms a dark red brittle mass which fumes strongly in the air its colour then changing first to bright vermilion-red and ultimately to snow-white. It melts easily and solidifies in the crystalline form on cooling. At a higher temperature it boils and distils over. In the state of vapour it appears to be colonrless. In water it instantly assumes a vermilion-red colour and is slowly decomposed. Bisulphide of carboii dissolves it in larger quantity forming a blood-red solution which when concentrated by distil- lation deposits the compound in dark red crystals.Hydrated Oxide of Silicon Si .0,2HO. -Produced in the decomposition of the preceding compounds by water e.g. Si2Cl,.2HC1 + 5H0 = 5HC1 + Si,03.2H0. It is most readily obtained as a secondary product in the prepara- C. 0'water must be cooled to The tion of the chloride (p. 92). as the oxide is decomposed by it at ordinary temperatures. The oxide is collected on a filter and washed with ice-cold water ;the filter gradually but strongly pressed between bibulons paper ; aid the oxide dried over oil of vitriol. It is a siiow-white amorphous body very light and bulky znd floats in water but sinks in ether. Alkalies even ammonia and their carbonates decomposes it with frothy evolution of hydrogen and formation of alkaline silicates.It is not acted upon by any acid except hydroflnoric acid which dissolves it with rapid evolu- tion of hyclrogeu. It may be heated to 300' C. or above without F. W~HLERAND H. BUFF giving off water or undergoing any other change. At a stronger heat it takes fire and glows brightly with a phosphorescent light giving off hydrogen gas which takes fire with explosion. Heated in oxygen gas it burns with a dazzling light. It likewise burns when heated in a covered crucible but the residual silica has more or less of a brown colour arising from admixture of amorphous silicon and the inner surface of the crucible becomes coated with silica. These appearances are due to the evolution and subsequent decomposition of siliciurett ed hydrogen.In fact when the com- pound is heated in a tube it gives off a gas which fumes in the air but does not take fire spontaneously in consequence of being mixed with free hydrogen; but when set on fire it burns with separation of silica. When the hydrate is dried in a stream of hydrogen then heated to redness and the gas which escapes is passed through a narrow tube heated to redness at one part, the tube becomes coated with a brown speculum of silicon and the escaping gas when set on fire yields a deposit of silicic acid on a glass plate held against the flame. If siliciuretted Iiydro-gen has the composition SiH the decomposition of the hydrated oxide may be represented by the equation 3(Si20,.2HO) = 5Si0 + 5H + SiH. Hydrated oxide of silicon is somewhat soluble in water The acid filtrate obtained in its preparation is constantly filled with rising bubbles of hydrogen presenting the appearance of fermenta- tion and the gas is evolved with such force as to project the stopper from the vessel if closed.The decomposition may be still further accelerated by heat. The solution also gives off abundance of hydrogen when mixed with ammonia. It is a powerful redu-cing agent. It precipitates gold and palladium from the solutions of their chlorides the latter perhaps mixed with silicate of'palladium. With nitrate of silver it first forms a white precipitate of chloride of silver but afterwards throws down a brown substance containing silicon as well as silver. Mixed with a cupric salt arid then with an alkali it throws down yellow cuprous hydrate.With corrosive sublimate it forms a precipitate of calomel which if left in con- tact with excess of the solution is gradually reduced to the grey metal. From selenious tellurous and sulphurous acids it preci- pitates respectively selenium tellurium and sulphur. It instantly decolorises a solution of permanganate of potash. It has no action on chromic acid or on solutions of platinum iridium or indigo. The composition of the hydrated oxide as given by analysis, agrees nearly with the above formula. Two aualyses gave in 100 parts 50.95 and 50.99 Si; 27-34and 27.68 0; 21.68 and 21-33 HO ; the formula Si,O,. 2H0 requiring 50.35 Si 28.37 0 and 21.28 HO. In some cases however a larger proportion ON SOME NEW COMPOUNDS OF SILICON.even 52-75 p. c. silicon was obtained and this together with cer-tain reactions of the compound leads to the supposition that there exists a lower oxide of silicon probably SiO and a corresponding chloride. The lower oxide appears to be that which dissolves in water and produces the reducing effects above mentioned ; a portion of the oxide which had yielded above 52 p. c. of silicon was again mixed with water and again washed on a filter with water at the ordinary temperature till the wash-water exhibited with nitrate of silver no longer a precipitate but merely a brownish colouring. The residual oxide was found to contain only 49.05 p. c. silicon. The chloride corresponding to the lower oxide (SiCl?) appears to be gaseous at ordinary temperatures.In one preparation amorphous silicon in considerable quantity was exposed to the action of hydrochloric gas at a temperature below redness. The reaction took place with great facility and hydrogen was abun-dantly evolved ; but the U tube though cooled to -15O C. was afterwards found to contain very little liquid chloride ; while on the other hand the water through which the gas passed after leaving the U tube contained a large quantity of white oxide which burnt with peculiar brightness yielding a brown coloured silica. This was the oxide which was found to contain 52-75 per cent of silica. Nitride ofSiZicon.*-This compound is obtained by the action of ammonia on either of the chlorides of silicon.It is perfectly white amorphous infusible and unalterable at the hightest temperatures and does not oxidise when ignited in contact with the air. It is not acted upon by alkalies in solution or by acids excepting hydrofluoric acid which converts it into silicofluoride of ammonium. When fused with hydrate of potash it gives off a larger quantity of ammonia and yields silicate of potash. Heated with red oxide of lead it reduces the lead with incandescence and formation of nitrous acid. Like nitride of boron it eliminates carbon from carbonic acid. Fused with carbonate of potash it yields silicate and cyanate of potash from which urea may be prepared; if the nitride of silicon is in excess cyanide of potassium is formed at the same time.* H. Sain te-Claire Deville and W ohler. Ann.Pharm. civ 356. 96 On Chloride of Ethylene.* By A. Wurtz. WHENpentachlorit 3 of phosphorus is gradually added to g,ycol which is kept cool a brisk action takes place; hydrochloric acid being evolved and the glycol being converted into a viscid mass without blackening. On adding more of the pentachloride the mixture becomes more fluid and after a certain time the erohtioii of hydrochloric acid ceases; and any additional quantity of the pentachloride dissolves in the liquid while hot but separates again 011 cooling. If the product be then distilled it begins to boil below 100"; bnt the boiling point gradually rises to above 150" and the residue ultimately blackens. The distillate is colourlcss arid when redistilled passes over completely below 115".It con-tains oxychloride of phosphorus which may be decomposed by agitation vi ith water and an oily liquid then separatesl whic!~ when washed with water dried by chloride of ca1cium and rectified exhibits the properties and cornpositiori of chloride of ethylene C,H,Cl,. Its formation is represented by the equation Chloride of ethylene stands to the bi-acid compound glycol in the same relation as chloride of ethyl to the mono-acid conipoiind alcohol. C,I160 + HC1 = H,O + C4€15Cl C,H60 + 213Cl = 2H,O + C,H,Cl it is the hydrochloric etlzer of glycol. * Compt. Rend. xlv. 228. Ann. Ch. Pharm. clv. 174.

ISSN:1743-6893    

DOI:10.1039/QJ8591100053

出版商:RSC    

年代:1859

数据来源: RSC

摘要:

INDEX A. Acetates and bromacetates of methyl, ethyl and amyl relationship between their boiling points 27. Acid acetic on the action of bromine on it by W. H. Perkin and B. F. Duppa 22. -amylonitrophosphorous 251. -bibromacetic 28. -bromacetic best mode of preparing it 22. -its action on ammonia 29. -carbonic estimation of it by means of manganate of potash 213. . preparation of propionic acid by its action on an ethyl-compound, by J. A. Wanklyn 103. -quantity of it in the air of Manchester and its neighbourhood arising from the combustion of coals 199. -dinitroethylic preparation of 85. -its products ofdecompofiition 87. -glycollic and glycocol their forma- tion from bromacetic acid 29 30. -hypochloric new method of pre-paring it by F.C. Calvert and E. Davies 193. -propionic its preparation by the action of carbonic acid on an ethyl-compound by J. A. Wanklyn 103. -rosolic note on by Hugo MiiIler 1. -sulphurous in smoke from com-mon fires 232. Acidity of the air at Manchester and other localities 209. Acids. distinctions beheen monoba sic and bibasic 3 27. -organic on a series of them con- taining nitrogen by E. Frank 1a n d ’19. Aesculin and paviin distinction be-tween 18. Air of towns by R. Angus Smith 196. -its effect on the bIood 224. -its effect on stones bricks 1 mortar etc. 232. Alkaloids on some compounds of iodide and bromide of mercury with the by T. B. Groves 97. -(cinchona) general characters of their iodosulphates 130.Amides and amines 254. Ammonia and its derivatives by A. W. Hofmann 252. -its action on bromacetic acid 29. -its amount in the air of towns 229. -basic derivatives of it constructed on the mater-type 2’70. -in smoke from common fires 232. -formation of organic bases by the direct substitution of organic radicals for the hydrogen in it 278 287. Ammonium bromscetate 23. Amyl action of nascent hydrogen on its nitrite 247. -action of phosphorus upon its nitrite 250. -action of potassium and of chlorine on its nitrite 248. -bromacetate of 26. -contributions to the knowledge of the amyl group by Frederick Guthrie 245. -nitrite of 245. Amylo-nitrophosphate of potash 251.Analysis on the use of gas as fuel in organic by A. W. Hofmann 30. Anniversary meeting (March 30 1858), 181. Antimony arsenic nitrogen and phos- plioriis bases compared 76. Arrows remarks on poison obtained from by H. J. B. Hancock 104. Arseniates of baqta lime and magnesia by F. Field 6. hrseniate of lime and ammonia 10. -of magnesia and ammonia 12. Arsenic its separation from antimony 16. -its separation from other elements by F. Field 6. ltmopyre. 31. itomic weight of carbon 129. -weights of oxygen and water by W. Odling 107. (1857-8) 191. Ball-soda or black ash its composition and analysis by J. JV. Kyn&ston, 155. Barium bibromacetate of 28. -bromacetate of 23. Baryta arseniate of 8.-dinitmethylate of 86. Bases comparison between antimony, arsenic nitrogen and phosphorus bases 76. -natural organic bases considered as derivatives of ammonia 265 267. -(organic) their formation by the direct Substitution of organic radicals for the hydrogen in ammonia 278 287. 1 Bssic derivatives of ammonia constructed on the water-type 270. Bibasic and monobasic acids distinctions between 127 Bibromace tates 28. Bichloramyl nitrite of 249. Binoxide of nitrogen action of zincethyl on 80. action of zincmethyl on 88. Biselenide of triethylphosphine 71. -trimethylphasphine 74. Bisulphide of triethylphosphine 69. -trimethylphosphine 74. Black ash or ball soda its composition and analysis by J. W. Kynaston 156.Blood effects produced upon it by the air of towns 221. Boiling p?ints of the acetates and bro- macetates of methyl ethyl and amyl 27. Bromacetates 23-27. Bromide of mercury its compounds with the alkaloids 97. -silicon and hydrogen 93. -triethylphosphine 69. Bromine its action on acetic acid by W. H. Perkin and F. B. Duppa 22. Buff and Wohler on some new com-pounds of silicon 90. C. Cahours and Hofmann researcheson the phosphorua-bases 56. Calcium bromacetate of 23. Calvert and Davies onanew method of preparing hypochloric acid or peroxide of chlohe 193. 402 IXDEX. 13. Carbon its atomic weight 129. -in the air of towns 230 Balance-sheet of the Chemical Society -on the surface of buildings etc.in large towns 233. Chemical action of water on soluble salts by J. H. Gladstone 36. Chemical Society. proceedings at its meetings 50 151. Chloride of ethylene by A. Wurtz 96. -silicon and hydrogen 91. -chloride of triethylphosphine 69. Chlorine its action on nitrite of amyl 248. .__ new method of preparing hypo- chloric acid or peroxide of chlorine by F. C. Calvert and E. Davies 193. Cinchona-alkaloids general characters of their iodosulphates by W. B. Hera-path 130. Cinchonidine formulze of 150. Cinchonine its compound with iodide of mercury 101. Cinnabar on a peculiar pseiidomorph of cinnabar from Pola de Lena in Asturia Spain by Hugo Miiller 240. Columbite frdm Evigtok in the Fiord of Arksut in Greenland 243 Copper bromacetate of 23.-dinitroethylate of 87. D. Davies and Calvert on a new method of preparing hypochloric acid or per- oxide of chlorine 193. Davy (Edmunct) obituary notice of 184. Diamines 261. Diammonium compounds 271. Dinitroethylates 83-87. Dinitromethylatcs 89. Double salts chemical action of water on bhem 46. I Duppa and Perkin on the action of bromine on acetic acid 22. Ether dinitroethylic 86. Ethyl bibromscetate of 29. -bromacetate of 25. -preparation of propionic acid by the action of carbonic acid on an etbyl-compound by J. A. Wan klyn 103. Ethylene on chloride of by A. Wurtz 96. INDEX. 483 F Ficld F. on the arseniates of baryta lime and magnesia and the separa- tion of arsenic from other elements 6.Frankland E. on a new series of or-ganic acids containing nitrogen 79. Fraxin compared with paviin 21. G. Gas on its use as fucl in organic analysis by A. W.Hofmann 30. Gladstone J. €I. on the chemical action of water on soluble salts 36. Glycocol its formation from bromacetic ataid 29. Gold-salt of tetrethylphosphonium 66. -tetramethy lphosphonium 74. Groves T. B. on som6 compounds of iodide and bromide of mercury with the alkaloids 97. Guthrie F. contributions to the know-ledge of the amyl-group 245. Hadow E. A. on the action of oxy-dizing agents on the sulphocyanides 174. Hancock H. J. B. some remarks on poison obtained from arrows 154. Herapath W.B. on the general cha- racters of the iodosulpIiates of tlic cinchona alkaloids 130.Hofmann. A. W. on ammonia and its derivatives 252. -on the use of gas as fuel in organic analysis 30. Hofmann and Cahoiirs researches on the phosphorus-bases 56. Horse-chestnut on the existenne of a second crystallizable fluorescent sub-stance (paviin) in its bark by G. CT. Stokes 17. Hydrated oxide of silicon 93. I_-tetramethylphosphonium ac-tion of heat on 74. -tetrethylphosphonium 65. -trietliylamylphosphonium ac-tion of heat on 72. Hydrogen action of nascent hydrogen on nitrite of ampl 247. -and silicon bromide of 93. -in ammonia its e!imination by the action of the bromide.; chlorides and iodides of the alcohol-radicals 278-287. VOL. XI. Hydrogen in ammonia its elimination by thc action of oxygen-compounds of organic radicals 287.and silicon chloride of 91. I_-iodide of 93 Hyposulphites process for the determi- nation of sulphides sulphite., hypo-snlphitca and sulphates in presence of each odier as adopted in the cleter- inination of these salts in soda waste as obtained from black ash by J. \V. Kynaston 168. I. Iodide of mercury its compounds with thc alkaloids 97. -methyltriethylphosphonium 71. -tctramcthylphosphoiiium 74. Iodo-cinchonine sulphate of 151. Iodo cinchonidine sulphate of 143. Iodo quinidinc preparation of its sulphate 1313. -snlphate of 140. Iodo-sulphate of quinine 133. Iodo-sulphates of the cinchona alkaloids their general characters by W.l3. Herapath 130. Iodide of triethglphosphine 69. -tetrethylplioapl~onium,64. -triethylainylphosphuniuni 71. -trimcthylamylphosplionium 75. -trimeth~!ethylpl~oiiium,75. Iron (meteoric \ from Zacatecas in Mexico annlysccl by H 11 g o JI ill 1e r 2‘36. K. Kynaston J. W. on the composition and analysis of black ash or 1~~11 sotla 155. -process for the quantitative cstiiiia-tion of sulphides sulphites hgpow I-phites and sulphatcs in presc.ncc of each other as adopted in the detmmi- nation of these salts in “soda waste ’ a2 obtained from black ash 166. L‘ Lead bibroniacctate of 25. -bromacehtc of 24. Liebetlienite from Congo in Portiigues Africa by Hugo Miiller 242. Liebig J. extract of a letter frotn to Dr.DauLeny on some properties of h011S 53. 2 1 404 INDEX. Lime its effect in diminishing the amount of sulphur evolved in the distillation of coal 234. -dinitroethylate of 87. ___ and ammonia arseniate of 10. M. Jf acvicar J. G.,notice of another nev maximum and maximum mercurial thermometer 106. Magnesia dinitroethylate of 57. -and ammonia armiiate oi’ 12. Mercury on some conipounds of its iodide and b?oomicle ~rlchthc alkaloids by T. B. Groves gi hIetalIamincs 302 Metallic deposits in chimneys of rever-beratory furnaces used for melting alloys of silver with copper and with gold by J. Kapier 368. Mcteoric iron from Zacatecas in Mexico analysed by Hugo Miillcr 236. lTethy1 brornacetate of 25. If ethyltrieth~lphosphonium,iodide of 71.RfineraIogical contributions by Hugo 11ullrr 236. Monamincs primary 255. -secondary 258. __ tertiary 259. Monobasic and bibasic acids distinctions between 127. Morphine its compound with iodide of mercury 99. 31ul I er H. mineralogical contributions 236. -note on rosolic acid 1. N. Napier J. remarks on metallic deposits found in two chimneys attached to reverberatory furnaces one being used for melting an alloy of silver and copper and the other an alloy of silver and gold 168. h’itride of silicon 95. Nitrite of amyl 245. -action of nascent hydrogen upon it 247. -action of potassium and of chlorine upon it 248. -I_ phosphorus upon it 250. Xitrite of bichloramyl 249.Nitrogen action of zinc ethyl on its bi-noxide 80. -zincmethyl on its binoxide 83. Nitrogen on a series or organic acids con- taining it by 13. Frankland 79. -phosphorus arsenic and antimony bases compared 76. 0. Odling W. on the atomic weights of qxygen and water 107. Obituary nutict> of Professor Edmund Davy 181. -Ihron ThBnard 182. Organic acids on a series of them contain- ing nitrogen by E. Frankland 79. -analysis on the ube of gas as fuel in by A. W. Hofmann 30. I_ bases their formation by the direct subatitution of organic radicals for the hydrogen in ammonia 278 287. -their formation by the reduc- tion of nitro-compounds 290. -~by the decomposition of nitro-gcccus substanccc 293. -matter estimation of it by means of manganate and permanganate of potash 217.Oxide of silicon hydrated 93. Oxidizing agents their action on sulpho-cyanides by E. A. Hadow 174. Osygen,itsamountinthe air of towns 228 -and water on the atomic weights of by W. Odling 107. Oxone in the air at &lanebester and other localities 209. P. Paviin a second crystallizable ffuores- cent substancc in the bark of the horse-chestnut by G. G. Stokes 17. Pentamines 268. Perkin and Duppa on the action of bromine on acetic acid 22. Pcroxide of chlorine new method of pre-paring it by F. C. Calvert and E. Davies 193. Phosphorus action of its terchloride on zinc-ethyl 59. -its action on nitrite of amyl 250. ~ nitrogen arsenic and antimony bLws compared 76.I_ hses researches on them by A. 7V. IIofinann and -1. Cahoure 56. Platinum-salt of tetramethylphospho-nium 74. -___ t,rimethylamylphosphonium, 76. -trimethglet hylphosphoninm, 75. ~-t~imetbylplios~~l~ine, 73. INDEX. 405 I’latinum salt of te trethylphosphonium 66. Poison obtained from arrows some re. marks onit by H. J. B. Hancock; 154. Potash amylonitrophosphite of 251. Potassium bromacetd,e of 23. -its action on nitrite of amyl 248. President’s report 181. Proceedings at the meetings of the Che. mica1 Society 50 181. Q* Quinine its compound with iodide of mercury 100. ~ iodosulphate of 133. Radicals (organic) formation of organic bases by the direct substitution of them for the hydrogen in ammonia 2’78 287.Rain impurities in it at Manchester and its neighbourhood 212. Report of the President and Council of the Chemical Society 181. -of the Treasurer of the Chemical Society 191. s. Salt (common) its influence on the amount of sulphur evolved from coal by distillation 235. Salts on the chemical action of water on soluble by J. H. Gladstone 36. Silicon and hydrogen bromide of 93 -chloride of 91. -iodide of 93. -hydrated oxide of 93. -nitride of 95. -on some new compounds of by F. Wohler and H. Buff 90. Siliciuretted hydrogen 90. Silver bibromacetate of 25. _I bromacetate of 25. __ dinitrocthylate of 87. Smith 13. d. on the air of towns 196. Smoke from common fires ammonia and sulphurous acid contained in it 232.Soda composition and analysis of black ash or ball soda by J. W. Kynaston, 155. __ dinitroethylate of S7. Soda dinitromethylate of 89. Soda-waste determination of snlphides sulphites hyposulphites and sulphates in soda-wabte” as obtained from “black wash,” by J. W. Kynaston 166. Sodium bromacetate of 23. Sotlium-ethyl action of‘carbonic acid on 103. -preparation of 103. Soils on some properties of by J. Liebig 53. Stokes G. G. on the existence of a second crystalliable flnorescent sub-stance (paviin) in the bark of the horse-chestnut 17. 3 Strychnine its compound with iodide of mercury 100. Sulphate of iodo-cinchonidine 143. -of iodo-cinchonine 151. -of iodo-quinidine 140.Sulphides process for the quantitativc detei mination of snlphides sulphites Iiyposulphites and sulphates in pre-sence of each other as adopted in the determination of these salts in “soda waste,” as obtained from “black ash,” by J. W. Kynaston 166. Sulphocyanides action of oxidizing agents upon them by E. A. Ha do w 174. Sulphur amount of it in coals used in Manchester 206. -influence of lime and common-salt in diminishing the amount of sulpliur evolved from coal by distillation 215. -acids in the air of RIanchester 206. T. Tarry matters in the air of towns 231. Terchloride of phosphorus its action on zinc-ethyl 59. Tetramethylphosphonium action of heat on its hjdrated oxide 74. -gold and platinum-salts of 74.-iodide of 74. Tetramines 268. Tetrethylphosphonium action of heat upon its oxide 66. -gold and platinum salts of 66. -hydrated oxide of 65. -iodide of 64. ThBnard (Baron) obituary notice of 182. Thermometer notice of a new maximum and minimum mercurial thermometer by J. G. Macvicar 106. 406 ISDEX. -hiselenide of $1. -bisulphidc of 69. -chloride bromide and iodide of 69. Triethylamylphosphonium action of heat on its hydrated oxide of 72. U. Ureas considered as diamines 262 Wanklyn J. A. on a new mode of preparing propionic acid viz. by thc constructed on it. 2i0. Wohlcr and Bug on some ncw com- pounds of silicon 90. W u rt z A on chloride of ethylene 96. Zinc dinit,roethylate of 84. __-and Lnc-ethyl 83. -dinitromethylate of 89. Zincethyl ite aciion on binoxide of ni-trogen 80. --action of terchloride of phos-phorus on it 59. Zincmethyl its action on binoxide of nitrogen 88. PHINTEL) UY IIAKEllbOY AND SONb 51. MAGIIN'S LANE W C

ISSN:1743-6893    

DOI:10.1039/QJ8591100401

出版商:RSC    

年代:1859

数据来源: RSC