摘要:

J 0 U R N A I, OP THE CHEMICAL SOCIETY. H. E. AEMSTRON(X, Ph.D., F.R.S. E. ATKINSON, Ph.D. A. CRUM BROWN, DSc., F.R.S. WYNDHAM R. DUNSTAN. H. MCLEOD, F.R.S. R. MELDOLA, F.R.S. H. F. MOBLEY, M.A., D.Sc. W. RAMSAY, PbD., F.R.S. J. MILLAR THOMISON, F.R.S.E. T. E. THOEPE, Ph.D., F.R.S. W. P. WYNNE, B.Sc. &hitar : C. E. GIZOVES, F.R.S. Spjub.-@bitor : A. J. GREENAWAY. Vol. LIX. 1891. TRANSACTIONS. LONDON: GURNEY & JACKSON, 1, PATE'RNOSTER ROW. 1891.LOiTDOX : KARRISOX AKD SONS,PHIRTERS I S ORDIFART TO HER NAJESTY, ST. MARTIP’S LAKE.C O N T E N T S . PAPERS READ BEFORE THE CHEMICAL SOCIETY. PAGE I.--Ethylic Phenanthroxylene-acetoacetate. By FRANCIS R. 11.-Contributions to the Knowledge of Mucic Acid. Part IV. Action of Phosphorus Pentachloride on Mucic Acid. By S .RUHERIANN, Ph.D., M.A., and S. F. DCFTOX, B.A., B.Sc. 26 III.--Notle on Normal and Iso-propylparatoluidine. By E. HOR~ and H. F. MORLEY . . 33 IV -A New Method of Determining the Specific Volumes of Liquids and of their Saturated Vapours. By SIDKEY YOUNG, D.Sc., Professor of Chemistry, University College, Bristol . . 37 V.-The Estimation of Cane-sugar. By C . O’SULLIVAN, F.R.S., and FREDERIC W. TOMPSON . 46 V1.-Action of Light on Pure Ether in Presence of Moist VI1.-Volumetric Estimation of Tellurium. Part I. By BOHU- SLAV RRAUFER, Ph.D., Professor in the Bohemian Univer- sity, late Berkeley Fellow of Owens College . . 58 VII1.-Note on Dibenzanilide. . Ry J. B. COHEN, Ph.D., Owens College, Manchester . . 67 1X.-Phenylbromacetic Acid, an apparent Exception t o the Le Bel-Van’t Hoff Hypothesis.By T. H. EASTERFIELD 71 X.-Action of Beat on Nitrosyl .Chloride. -By J;. J. SUDBOROUGH, H.Sc. (Lond.), A.I.C. (Associate of the Mason College), and J. IT. MILLAR . . . . 73 XI.-The Fermentation of Calcium Glycerate by “ Bacillus Ethaceticus.” By PERCY F. . FRAKKLAXD, Ph.D., B.Sc. (Lond.), F.I.C., Professor of Chemistry in University College, Eundee ; St. Andrews University ; and WILLIAM FREW, F.C‘.S. . . 81 XI1.-An Optically Active Glyceric Acid. By PERCY F. FRAKK- LAND, Ph.D., B.Sc. (Loxd.), F.I.C., Professor of Chemistry ill University College, Dundee ; St. Andrews University ; and WJLLIAN FREW, F.C.S. . 06 JAPP, F.R.S., and FELIX KLINGEMANN, Ph.D. . . 1 Oxygen. By A.. RICHARDSON, Ph.D. . . . . 52iv CONTENTS. XII1.-Condensation of Acetone-phenanthraquinone.By G. H. WADSWORTH, Associate of the Royal College of Science . XIV.-The Spectra of Blue and Yellow Chlorophyll, with some Observations on Lea€-green. By W. N. HARTLLY, F.R.S., Professor of Chemistry, Royal College of Science, Dublin. XV.-The Molecular Volumes of the Saturated Vapours of Benzene and of its Halogen Derivatives. By SYDNEY YOUNG, D.Sc., Professor of Chemistry, University College, Bristol . . . XV1.-The Action of Ammonia and of Methylamine on the Oxplepidens. By FELIX KLINGEMANN, Ph.D., and W. F. XVI1.-Contributions from the Laboratories of the Heriot Some Derivatives of Piperonyl. XVII1.-The a- and @Modifications of Benzene Hexachloride. By F. E. MATTHEWS, Ph.D.. X1X.-The Action of Heat on Ethylic P-Amidocrotonate.Part I. By J. NORMAN COLLIE, F.R.S.E. . , XX.-On the Constitution of Dehydracetic Acid. By J. NORMAN COT~LIE, Ph.D., University College, London XX1.-Phenuvic Acid ; Contributions to our knowledge of its Constitution, and Relationship with the Phenylmethylfur- furancarboxylic Acid of Paal. By ARTHUR COLEFAX, B.A., Ph.D., late Natural Science Postmaster of Merton College, Oxford . a m . . XXIL-Magnebic Rotation. SXII1.-Action of Phosphoryl Chloride on Phosphorus Pent - oxide. By G. N. HUNTLY, Assoc. R.C.Sc. (Lond.) . XX1V.-Chlorinated Phenylhydrazines. By 5. T. HEWETT, B.A., B.Sc., Assoc. R.C.S. . XXV.-Action of Reducing Agents on ad-Diacetylpentane. Synthesis of Dimethyldihydroxyheptamethylene. By F. STANLEY KIPPING, Ph.D., D.Sc., and W. H. PERKTN, Jun., XXV1.-Contributions from the Laboratory of Gonville and No.XIX. Compounds of the By R. XXVI1.-Crystalline Form of the Calcium Salt of the New Optically Active Glyceric Acid. By ALFRED E. TUTTOR, Assoc. R.C.S., Demonstrahor in Chemistry at the Royal College, of Science, London . XXVIIL-Volumetric Estimation of Tellurium. Part 11. By BOHUSLAV BRAUNER, Ph.D., Professor in the Bohemian University, Late Berkeley Fellow of Owens College . LAYCOCK, Ph.D. . . . . By FREDERICK M. PERKTN . . . . . Watt College, Edinburgh. . By W. OSTWALD . Ph.D., F.R.S. . . . . . . Caius College, Gambridge. Oxides of Phosphorus with Sulphuric Anhydride. H. ADIE,M.A. , . . . . . . . PAQB 105 106 125 140 150 165 172 1'19 190 198 202 209 214 230 233 238CONTENTS. v PAGE XX1X.-Fermentations indriced by the Pneurnococcus of Fried- Iiinder.By PERCY F. FRANKLAND, Ph.D., B.Sc. (Lond.), Asmc.R.S.M., F.I.C., ARTHUR STANLEY, F.C.S., and WILLIAM FREW, F.C.S. . . . * A Correction. Action of Heat on Kitrosyl Chloride, By J. J. SUDBOROUGH and J. H. M~LLAR , . . XXX.-Contributions to our Knowledge of the Aconite Alkalo’ids. Part I. On the Crystalline Alkaloid of Aconifum napellus. By Professor W. R. DUNSTAN and XXX1.-Crystallographical Characters of Aconitine from Aconitum napellus. By ALFRED E. TUTTOP;, Assoc. R.C.S., Demonstrator in Chemistry at the Royal College of Science, London . . . . . XXXI1.-Molecular Refraction and Tlispersi m of various Sub- stances. By J. H. GLADSTONE, Ph.D., P.R.S. . XXXTI1.-Citraconfluoresce’in. By J. T. HEWITT, B.A., B.Sc., Assoc.R.C.S. . . XXX1V.-The Oxidation of Mannitol by Nitric Acid. d.-Man- nosaccharic Acid. By T. H. EASTERFIELD, B.A. (Junior Demonstrator in the University Laboratory, Cambridge) . XXXV.--Studies of the Terpenes and Allied Compounds. The Nature of Turpentine Oils, including that obtained from Pinus Khasynna. By HENRY E. ARM~TROKG . XXXV1.-Studies of the Terpenes and Allied Compounds. Sobrcrol, a Product of the Oxidation of Terebenthene (Oil of Turpentine) in Suulight. By HENRY N. ARMSTRONG and XXXVI1.-A Rapid Method of Estimating Nitrates in Potable mTaters. By GhORGE HARROW, Ph.D., F.1.C. . XXXVII1.-Some Compounds of Dextrose with the Oxides of Kickel, Chromium, and Iron. By ALFRED C. CHAPNAN . XXX1X.-Action of Acetic Acid on Phenylthiocarbimide. By J. C. CAIN and J.B. COHEN, Ph.D., Owens College, Man- Chester . XL.-Ethyl Thiacetoacetate. By CHARLES T. SPRAGUE, B. Sc., Ph.D.. XL1.-On the Osmotic Pressures of Salts in Solution. By R. H. ADIE, M.A., Trinity College, Cambridge XLII.--Notes on the Azo-derivatlives of /%Naphthylamine. No. I. By RAPHAEL MELLDOLA, F.R.S., and FRANK HUGHES. XLII1.-On Some New Addition Compouiids of “ Thiocarb- amide ” which afford Evidence of its Constitution. By J. ENERSON REYNOLDS, M.D., F.R.S., Professor of Chemistry, University of Dublin . . . W. H. INCE, Ph.D. , . * . . . . W. J. POI’E . A 2 253 270 2 71 288 290 303 306 311 31 5 320 323 327 329 344 372 383vi COSTENTS. 1 XL1V.-Action of Acetic Anhydride on Substituted Thiocarb- amides, and on an Improved Method for Preparing Aromatic Thiocarbamides.By EMIL A. WERNER, Assistant Lecturer in Chemistry, Trinity College, University .of Dublin . . XLV.-The Action of Alkalis on the Nitro-compounds of the Paraffin Series. Formation of Isoxazoles. By WTNDHAM R. DUNSTAN and T. S. I)YMONU . Annual General Meeting . . XLV1.-The Addition of the Elements of Alcohol to t,he Ethereal Salts of Unsaturated Acids. 13s ‘1’. PURDIE, Ph.D., B.Sc., Professor of Chemistry in the United College, University of St. Andrewn ; and W. MARSHALL, B.Sc. XLVlI.--On Nitrification. Part IV. Ry R. WARISGTON, F.R.S. XLVIIL-The Iodometric Estimation of Nitric Acid in Nihrstes. By GEORGE MCGOWAN, Ph.1). . XL1X.-The Decomposition of Silver Chloride by Light. By A. RICHARDSOX, Ph.D., University College,. Bristol . L.-Interaction of Pheiiylthiocarbimide with Acetic and Prop- ionic Acids respectively. By EMIL A.WERNER, Assistant Lecturer in Chemistry, University of Dublin LL-New Benzylic Derivatives of Thiocarbamide. By Aumsws E. DIXON: M.D., Professor of Chemistry, Queen’s College, Galwsiy . LI1.--Ethyl a&’-Dimethyl-a%’-diacetylpimelate and its Decom- position Products. By F. STANLEY KIPPING, Ph.D., D.Sc., and J. E. MACKENZ~E, B.Sc. LII1.-The Molecular Refraction and Dispersion of Various Substances in Solution. By Dr. J. H. GLADSTOSE, F.R.S. . L1V.-Volatile Platinum Compounds. By W. PULLING ER, Brackenbury Scholar of Balliol College, Oxford. LV.-Note on a Volatile Compound of Iron with Carbonic Oxide. By LUDWIG MOKD, F.R.S., and FRIEDRICH QUIXCI(E, Ph.D.. LVI.-The Lactone of Triacetic Acid.Ry J. NORMAN COLLIE, Ph.D., F.R.S.E., University College, London . LVI1.-Some Reactions of Dehydracetic Acid. By J. NORMAN COLLIE, Ph.L)., F.R.S.E., University College, I~ondon . LVII1.-Dibenzyl Ketone. By STDXEY YOUNG, D.Sc., Professor of Chemistry, Uiiiversity College, Bristol . L1X.-On the Vapour Pressures of Dibenzyl Ketone. By SYDNEY YOUNG, D.Sc., Professor of Chemistry, University College, Bristol . By SYDNEY YOUNG, D.Sc., Professor of Chemistry, University College, Bristol . . . LX.-The Vapour Pressures of Mercury. PAQE 410 434 4.68 4s4 530 5% 544 551 5G9 389 59s 604 607 61 7 6’21 626 ti29CONTENTS. Vii PAGB LXI.-Action of Nitric Acid on Anthracene. LXI1.-Researches on the Terpenes. On Camphene. By J. E. MARSH, M.A., Balliol, and J. A. GARDNER, Magdalen College LXIIL-Action of Nitrosyl Chloride on Metals.By J. J. SUDBOROUGH, B.Sc., A.I.C., Associate of Mason College, LX1V.-The Influence of Temperature on Germinating Barley. LXV.-Researches in the Triazine Series. By RAPHAEL MEL- LXV1.-The Action of Picric Chloride on Amines in Presence of Alkali. By 0. S. TURPIN, M.A., D.Sc. . , . . 714 LXVI1.-Researches on the Terpenes. 11, On Turpentine. By J. E. MARSH and J. A. GARDNER . . . , 725 LXVII1.-On Diphenylisosuccinic Acid and p-Diphenylpro- pionic Acid. Ry G. G,. HENDERSON, D.Sc., M.A., F.I.C., Assistant to the Professor of Chemistry, University of Glasgow . . . . . . . . 731 LX1X.-Contributions from the Chemical Laboratory of Edin- burgh University. No. 111. Preparation and Properties of E thy1 Hydrogen Pumarate and Ethyl Hydrogen Maleate.LXX.-Contributions from the Laboratory of Gonville and Caius College, Cambridge. No. XX. Action of Ammonia on Ethereal Salts of Organic3 Acids. By S. RUHEMAKK, Ph.D., M. A., University Lectnrer in Organic Chemistry, and R. S. MORRELL, B.A., latg Scholar of Caius College LXX1.-Contributions from the Laboratory of Gonville and Caius College, Cambridge. No XXI. Contributions to the Knowledge of Mucic Acid. By S. RGHEAIASK, Ph.D., M.A., and S. F. DU‘FTON, B.A., B.Sc. . . 750 LXXI1.-Contributions from the Laboratoiy of Gonville and Cftius College, Cambridge. No. XXII. Orthoquinoline- hydrazine. Bey S. F. DGFTOK, B.A., B.Sc., Assistant Demonstrator in the Cambridge University Chemical LXXII1.-Contributions from the Chemical Laboratory of the University of Edinburgh.No. IV. Oxidation of Cobalt Salts by Electrolysis. By HUGH MARSHALL, D.Sc,, F.R.S.E. 760 LXX1V.-Contributions from thc Chemical Laboratory of the University of Ndinburgh. No. V. The Persulphates. By HUGH MARSHALL, D.Sc., F.R.S.E. . . 771 LXXV.-Contributions from the Laboratories of the Heriot Watt College, Edinburgh. Acetylcnrbinol. By W. H. PERKIN, Jun., Ph.D., F.R.S. . . 786 By A. G. Perkin 634 648 Birmingham . . . . . . . 655 By T. CUTHBERT DAY . . . , 664 DOLA, F.R.S., and MARTIN 0. E’ORSTER . . 678 By JOHN SHIELDS, Ph.D., B.Sc. . , . . . . 736 . 743 Laboratory. . . 756... Vlll CONTENTS. PAGE LXXV1.-Contributions from the Laboratories of the Heriot Watt College, Edinburgh. Action of Methylene Iodide on the Disodium Compound of Ethyl Pentanetetracarboxylate.Synthesis of Hexamethylene Derivatives. By W. H. PEBK~N, Jun., Ph.D., P.R.S. . . 798 LXXV11.- Contributions from the Laboratories of the Heriot Watt Colle'ge, Edinburgh.' Syhthesis of - Homolopes of Pentanetetracarboxylic Acid and oE Pimelic Acid. By W. H. PERKIN, Jun., Ph.D;, F.B.S., and BERTRAM PRENTICF:. LXXVII1.-T he Synthetical Formation of Closed Carbon Chains. Part I (continued). The Action of Ethylene Bromide 011 the Sodium Compounds of Ethyl Acetoacetate apd Ebhj-1 genzoylacetate. By T. RHYMER MARSHALL, D.Sc., LXXIX.,The Grayivolumeter, an Instrument by means of which the Observed Volume of a Single Gas gives directly LXXX.-On the Vapour Pressures arid Molecular Volumes By SYDNEY YOUNG, D.$c., Professor of LXXX1.-On t h e Vapour Pressures and Molecular Volumes of Carbon Tetrachloride and Stannic Chloride.By ?WNEI- YOUNG, D.Sc., Professor of Chemistry, University College, Bristol . . 911 LXXXI1.-On the Freezing Points of Triple Alloys of Gold, Cadmium, and Tin. By C. T. HEYCOCK, M.A., and I?. H. NEVILLE, &LA. . . . . 936 By J. E. MARSH, M.A., Ba,lliol College, and H. H. CousrNs, B.A., Merton College, Oxford . . 966 LXXX1V.-Eulyte and Dyslyte. (A Correction.) By HENRY BAS SETT . 978 LXXXV.-The Magnetic Rotatory Power of Solutions of Am- monium and Sodium Salts of some of the Fatty Acids. LXXXV1.-Contributions f rorn the Laboratories of the Heriot Watt College, Edinburgh. New Synthesis of tlie Hexa- methylenedicarboxylic Acids. By W. H. PERKIN, Jun., LXXXVI1.-Contributions from the Laboratories of the Herio t Watt College, Edinburgh.Benzoylacetic Acid and some of its Derivatives. Part V. By W. H. PERKIN, Jun., Ph.D., F.B.S., and JAXES' S,TENHOUSE . . 996 LXXXVII1.- Contributions from the Laboratories of the Heriot Watt College, Edinburgh. Note on the Formation of Anthraquinone from Orthobenzoylbenzoic Acid. By W. H. 818 and W. H. PERKIN, Jun., Ph.D., F.R.S. . . 853 the Weight of the Gas. By FRANCIS R. JAPP, F.R.S. . . 894 Chemistry, University College, Bristol . . 903 0;f Acetic Acid. LXXXII1.-The Sulphonic Deriratives of Camphor By W. H. P E R K I N , Fh.l>., F.R.S. . . $31 Ph.D., F. R.S., and BEnTRAir PRENTICE . . . . 990 PEREIN, Juii., Ph.D., P.R.S. . . 1012CONTENTS. ix PAQE LXXX1X.-The Ortho- and Para-nitro-derivatives of Ortho- toluidine.By ARTHUR G. GREEK and THOS. A. LAWSON, Ph.D. . 1013 XC.-Phosphorous Oxide. Part 11. By T. E. THORPE, F.R.S., and A. E. TUTTON, Demonstrator of Chemistry at the Royal Part 11. Geddic Acids, Gedda Gums ; the Dextrorotatory Varieties. By C. O’SULLIVAN, F.R.S. . . . 1029 XCI1.-Dissociation of Liquid Nitrogen Peroxide. By J. TUDOR CUNDALL, B.Sc., Lecturer on Cheniistry in the Edinburgh Academy . . 1076 XCTLT.-On Iron Carbonyls. By LUDWIG MOND, F.R.S., and CARL LANGER, Ph.D. . . 1090 XC1V.-Note on some Compounds of the Oxides of Silver and By EMILY ASTON, B.Sc. (Lond.), Chemical Depart- ment, University College, Gower Street . . . . . log? XCV.-A New Method of Preparing p-Dinaphthylene Oxide, CmHIBO, and the Constitution of its Tetrasulphonic Acid. By W. R. HODGKIKSON mid L. LLMPACH . . 1096 College of Science, South Kensington . . 1019 XC1.-Researches on the Gums of the Arabin Group. Lead.CONTENTS. ix PAQE LXXX1X.-The Ortho- and Para-nitro-derivatives of Ortho- toluidine. By ARTHUR G. GREEK and THOS. A. LAWSON, Ph.D. . 1013 XC.-Phosphorous Oxide. Part 11. By T. E. THORPE, F.R.S., and A. E. TUTTON, Demonstrator of Chemistry at the Royal Part 11. Geddic Acids, Gedda Gums ; the Dextrorotatory Varieties. By C. O’SULLIVAN, F.R.S. . . . 1029 XCI1.-Dissociation of Liquid Nitrogen Peroxide. By J. TUDOR CUNDALL, B.Sc., Lecturer on Cheniistry in the Edinburgh Academy . . 1076 XCTLT.-On Iron Carbonyls. By LUDWIG MOND, F.R.S., and CARL LANGER, Ph.D. . . 1090 XC1V.-Note on some Compounds of the Oxides of Silver and By EMILY ASTON, B.Sc. (Lond.), Chemical Depart- ment, University College, Gower Street . . . . . log? XCV.-A New Method of Preparing p-Dinaphthylene Oxide, CmHIBO, and the Constitution of its Tetrasulphonic Acid. By W. R. HODGKIKSON mid L. LLMPACH . . 1096 College of Science, South Kensington . . 1019 XC1.-Researches on the Gums of the Arabin Group. Lead.

ISSN:0368-1645    

DOI:10.1039/CT89159FP001

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

26 RUHEMANN AND DUFTON: ACTION O F II.-Co&ibutions to the Knowledge of Mucic Acid. Part IT. Action of Phosphorus Pentachloride 0% Muck Acid. By S. RUHEMANN, Ph.D., M.A., and S. F. D UFTON, B.A., B.Sc. THE investigation described in this paper was anggested by the experiments which one of us carried out in conjunction with W. J. Elliott, with the object of isolating the substances formed along with dichloromuconic acid, when mucic acid is treated wit'h phosphorus pentachloride in the manner described by Bode. The result of the inquiry was the discovery of an acid isomeric with that found by this chemist and called by us p-dichloromuconic acid (Trans., 1890, 931). Guided by the view that the chlorides of these two acids cannot be formed directly by the action of phosphorus pentachloride on mucic acid, but result from tlhe splitting off of hydrogen chloride fromPHOSPHORUS PENTACHLORIDE ON MUCIC ACID.27 tetrachioradipyl chloride, which may be formed as an intermediate product, we studied +he action at a lower temperature than that recommended by Bode. Though under these circumstances me found that tetrachloradipjl chloride is not formed, yet a few experiments led to observa,tions which seemed interesting enough to pursue. Pho.~~J2.odichlol.omuconic Acid. Phosphorus pentachloride has hardly any action on dry mucic acid at the ordinary temperature, b u t on adding phosphorus oxychloride t o a mixture of 6 mols. of the chloride with 1 mol. of the acid, a slight evolution of heat takes place, and hydrogen chloride is given off.The reaction, when allowed to continue without warming, comes to an end after about 24 hours. The flask now contains a white, crystal- line substance suspended in the oxychloride, and also some unaltered phosphorus pentachloride which collects on the bottom of the vessel. On pouring off the oxychloride and the crystalline product suspended in it from the pentachloride, and gradually adding the mixture to powdered ice, the crystals are left undissolved. The latter are, how- ever, slowly dissolved by cold water, =ore rapidly when heated, with the exception of a small quantity of a white powder which is no doubt unchanged muck acid; the aqueous filtrate does not deposit any a-dichloromuconic acid, so that, under the conditions described above, no dichloromuconyl chloride is formed.On carefully con- centrating the solution on the water-bath, or in a vacuum ovez" salphuric acid, large, colourless, rhombic crystals separate out, which are very soluble in water and alcohol, the solution having a strongly acid reaction. For analysis the recrystallised substance was dried in air, and gave numbers corresponding with the formula C6H4CI204,2H3P04 + 4H20. Found. r---&-- -3 Theory. I. 11. 111. IT. C . . 15.24 15.26 - - ...... 15.03 H ........ 3.76 3.33 3.80 - C1. ...... 14.82 - - 15.02 - P ........ 12-94 I - - 12-75 - On drying over sulphuric acid in a vacuum, this compound lost in weight 11.31 per cent., corresponding to 3 mols. H,O, which require 11-27 per cent. On drying at loo", a further loss of 3.74 per cent. took place, corresponding to 1 mol.H,O, which requires 3.76 per cent. The anhydrous acid melts with decomposition at about 185".28 RUHEMANN AND DUFTON: ACTION O F Mr. R. H. Solly has been kind enough t o provide us with the following crystallographic data sf this acid. FIG. 1. System : Orthorhombic- a : 7, : c = 0.62812 : 1 : 0.29274. 100 : 110 = 0.32" 18'; 010 : 011 = 73" 41'; 001 : 101 = 24" 57'. Forms observed- dO0, b010, plll, nlO1, e011. up.. .... 66" 3' 66" 3' 7 66-66" 9' Obsemed. Calculated. No. of edges. Limits. bp ...... 74 13 74 13 7 74" 1'-74" 20' pp,, .... 58 36 58 30 5 58 8-59 2 No measurements were obtained from 17, and e. The crystals are limpid, the faces are always pitted, the a and b faces have good lustre, but the p planes are usually rounded and give poor reflections.The a and b faces are often evenly developed, but the p ones are peculiarly unequally developed, resembling crystals of the mineral meionite at one end of the c axis ; but have the planes parallel to the c plane evenly developed as shown i n the figure. The faces TL and e are very narrow and truncate the edges of ppi and p , and p , p,,. Cleavage a fairly perfect. Optical characters AE = b. 1st mean line a. Sign of double refraction positive. The optic angle iii air for Na 75" 25' ; p< v, weak. The formula given abme represents this acid as a compound ofPHOSPHORUS PENTACHLORIDE ON MUGIG ACID. 29 dichloromuconic acid with phosphoric acid ; it may, therefore, be called phosphodichloromuconic a,cid. The phosphoric acid is chemi- cally combined in the molecule, and cannot be detected by magnesia mixture, but the acid gives a yellow precipitate with ammonium molybdate when previously heated with nitric acid.The new acid contains in its molecule dichloromuconic acid, for on warming it with concentrated sulphuric acid, or by heating the aqueous solution in a sealed tube at 100" for several hours, a-di- chloromuconic acid is produced. On account of the new substance nndergoing decomposition in this way, it is necessary, in its prepara- tion, to concentrate the aqueous solution at a low temperature, otherwise part of it undergoes the same change. I f we accept for dichloromuconic acid the generally adopted, thongh not yet proved, expression C 0 OH* CH: C C1* C C1: CH*C 0 0 H, the phospho-acid may be represented by the formula C 0 OH*CH( OH)*CCl (H,POs)*C C1 (HJ?Os) 'CH (OH) CO OH.That the two molecules of phosphoric acid are distributed in this manner is supported by the following experiments. The phosphodichlororouconic acid has, as stated before, a strongly acid reaction. A solution of 0,0864 gram of the acid required for neutralisation a volume of titrated potash containing 0.0403 gram KOH, which corresponds to 46.64 per cent. KOH. This shows that 4 rnols. of KHO (46.76 per cent.) are required to neutralise 1 mol. of the acid, If, however, potash is added to an excess of the acid dis- solved in water, colourless crystals of ZL salt containing two atoms of potassium separate out. The formula C6HsK1CI,P2012 requires :- Found. r----- 7 Theory. I. 11. K ......... .. 16-15 16.6 16-37 This potassium salt has, as might be expected, acid properties ; it is sparingly soluble in cold, more readily in boiling water. Barium SaZt.-If barium chloride is added to a solution of the phospho-acid, a barium salt is precipitated after some time in colour- less crystals which, once formed, are only slightly soluble in water. This salt contains two atoms of barium and has, when dried at loo", the composition C6H,Ba2C12P,012 + H20, as indicated by the following analyses :-30 RUHEMANN AND DUFTON: ACTION O F Found. 7 r-.-.-"- Theory. I. 11. 111. Ba.. ...... 39.42 39-40 39.20 39.43 The salt does not lose its water of crystallisation at 140°, and decom- poses at a higher temperature. Aniline Xak-In an alcoholic solution of the acid, aniline produces a white precipitate which, washed with alcohol and dried at loo", has the formula C6H4C1,04,2H3P 04,2 C6H,*NHz. Found.r-- 7 Theory. I. 11. - N ............. 4.72 4.95 c1. ............ 11-97 - 12-22 This salt crystallises from water in colourless prisms, and its solu- tion is acid to litmus paper. The composition of these salts shows that two or four hydrogen atoms in phosphodichloromuconic acid are capable of undergoing substitution. According t o the formula for the acid given above, it should have six replaceable hydrogen atoms, and indeed i n the ammonium salt, we have a compound containing 6 mols. of NH,. Anwnoniuin XaZt.-This is formed by adding an excess of aqueous ammonia to the solution of the acid in water, when, if the solutions are concentrated, the salt is thrown down a t once in the form of colourless, oblique crystals, These lose their lustre on drying over sulphuric acid, and give off ammonia when heated alone or with w a h .For analysis, they were dried in air, aud gave numbers correspor;d- ing with the formula C6H4CI20,,2H3PO~,6NH3 + 5H,O :- Found. 7 r--A-- Theory. I. 11. 111. N ......... 14-02 14.32 - P.. ........ 10.35 -- 10.28 - - - c 1 . ........ 12-02 - 11.87 The properties and the composition of the salts of phosphodichloro- muconic acid, and especially those of the ammonium salt, support the view expressed above of the constitution of the acid ; it is to be re- garded as hexabasic, and may be formulated- COOH*CH( OH)*CCl( H,PO,) * CC1( HZPOs)*CH( OH) *COOH, i f the formula for dichloromuconic acid, GO 0 H* C I11 C C1* C C1: CH* C 0 0 H,PHOSPHORUS PENTACHLORIDE ON MUCIC ACID.31 be correct. This view is confirmed by the study of the product, which, iurder the influence of water, is transformed into the phospho- acid. Phosphoclichlorornuconyl Chloride. The action of phosphorus pentachloride and oxychloride on mucic acid at the ordinary temperature gives rise to a product which still contains a small quantity of unchanged mucic acid. The observation that the crystalline snbstance, thus formed, is soluble in warm phosphorus oxychloride gave the key to a method for its purification. If the mixture obtained in the reaction be heated to loo", and quickly filtered through glass wool, the clear liquid, on cooling, deposits colourless plates which, collected, washed with dry benzene, and dried over sulphuric acid, gave numbers corresponding with the formula COC1*CH(OH)*CC1(POC12)*CC1( POC12)*CH(OH)*COCl. Fonnd.7 rpA-- Theory. I. 11. 111. 14.15 - - C ........ 13.90 H ........ 0.77 0.85 - Cl.. ...... 54.82 - 54.56 - - P ........ 11-97 - - 12-17 This substance is identical with the crystals formed in the cold. It dissolves in water without leaving any residue, and the solution on concentration deposits the characteristic rhombic crystals of phospho- dichloromuconic acid. The fact that the former compound is stable at 100" allows of its preparation without using phosphorus oxychloride. Bode had already observed that the action of phosphorus pentachloride on mucic acid starts at 70" and is completed at 100".If the almost clear liquid, thus Gbtained, be quickly filtered, the above mentioned com- pound will crystallise out on cooling. The formation of this substance and the transformation it under- goes when treated with water show that the action of phosphorus pentachloride on mucic acid differs with the temperature : at loo", the phospho-acid chloride is produced ; at 120°, dichloromuconyl chloride. It was, therefore, to be expected that the product formed at a lower temperature mould, when heated with phosphorus penta- chloride at 120", yield dichloromuconyl chloride. This is indeed the case ; a mixture of 1 mol. of the former and 2 mols. of phosphorus pentachloride, when digested at 120°, evolves hydrogen chloride ; the32 ACTION OF PHOSPHORUS PENTACHLORIDE ON MUCIC ACID.mass becomes liquid, and on cooling deposits dichloromaconyl chloride ; the reaction may be expressed by the equation :- COCl*CH(OH)*CCl (POC&,)*CCI( POCl,)*CH( OH).CO Cl + 2PC15 = COCl*CH:CCl~CCl:CH*COCl + 4POC1, + 2HCl. This chloride, on the addition of water, is transformed into the characteristic needles of a-dichloromuconic acid. The latter may also be obtained from the phosphodichloromuconyl chloride by warning with concentrated sulphuric acid, when it dissolves, and, on pouring into water, Bode's acid is precipitated. Whilst t,he ph osphodichloromuconyl chloride yields, by the action of water, the phospho-acid, i t sufl'ers a different transformation under the influence of alkali or ammonia, and these changes throw light upon the relatioriship between Bode's dichloromucoriic acid and the /%acid.On adding phosphodichloromuconyl chloride to potash, it dissolves with evolution of heat, and addition of hydrochloric acid to the cold solution precipitates a-dichlorornuconic acid. The filtrate from this acid, when extracted with ether, yields the p-acid. Aqueous ammonia acts violently upon the phospho-acid chloride forming the amides of a- a'nd p-dichloromuconic acids, which are precipitated as a white powder in the course of the reaction. Their separation was effected by extracting with boiling water ; the hot filtrate, on cooling, deposits colourless needles, which by their pro- perties and a nitrogen determination were recognised as p-dichloro- muconamide. The formula CtiHtiClzN,Oz requires :- Theory.Found. N ................... 13.40 13.66 The residue left undissolved by water is sparingly soluble in alcohol, and is the amide of a-dichloromuconic acid, as indicated by the following nitrogen determination, which gave :- Theory for C,H,Cl,N,O,. Pound. N ................. 13.40 13-70 If, on the one hand, the observations described above explain satis- factorily the action of phosphorus pentachloride on mucic acid, on the other hand, they throw light upon the relationship between a- and p-dichloromuconic acids. Both acids are produced from the phospho-acid chloride, which, on treatment with water, yields only one phospho-acid, as indicated by the crystallographic measurements ; they are, therefore, most probably stereochemicnl isomerides.ON NORMAL AND ISO-PROPYLPARATOLUIDINE. 33 This view is confirmed by the ready transformation of the @-acid into Bode’s dichloromuconic acid.On adding a small quantity of bromine-water to a cold aqueous solution of the former, and allowing the mixture to stand for some time, the whole sets to a mass of crystah which do not contain bromine, but are simply a-dichloro- muconic acid, as indicated by its properties and by the following analysis :- The formula C,H4C1202 requires :- Found. r--A- 7 Theory. I. 11. C ........... 34-12 34-09 H 2-00 - ............ 1-90 C l . . .......... 33.65 - 33.62 - The isomeric dichloromuconic acids may be regarded, therefore, as bearing the same relation t o one another as fumaric to maleic: acid, the latter being completely changed into fumaric acid, by the action of haloid acids (KekulB, ,4nnaZen, Suppl. 1, 134), and, partially, by bromine (Petri, AnnaZen, 195, 59). If Wislicenus’ view with regard to the transformation of male’ic acid into fumaric acid be accepted, that one molecule of t,he lznlogen or haloid acid is first added, that then rotation of the system takes place, and that finally the halogen or halo’id acid splits off again, leaving the isomeric acid, then we may assume the change of p-dichloromuconic acid into the a-acid to be brought about by bromine in the same manner. University Laboratory, Cambridge,

ISSN:0368-1645    

DOI:10.1039/CT8915900026

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

33 ON NORMAL AND ISO-PROPYLPARATOLUIDINE. 111.-Note on Nornznl arid Iso-23l"opyl~aTatoluidine. By E. HORI and H. F. MOIZLEY. IK connection with an investigation which we undertook three o r four years ago, we thought it desirable to be able t o distinguish with certainty between normal and iso-propylparatoluidine. We had completed the examination of this point when the .investigation of which this was to form a part was brought to an abrupt termination by the departure of one of us from England. Nevertheless, we think that. t'he following observations, made in 1887, ought, perhaps, to be recorded. FOL. LIX. D33 HORI AND MORLEY ON NORNAL Isoprop ylparatoluidine. An almost theoretical yield of isopropyltoluidine may be obtained by heating isopropyl iodide with paratoluidine in equimolecular proportions f o r two days in sealed tubes at 130". The isopropyl iodide employed was obtained i n the usual way from glycerol, iodine, and amorphous phosphorus, and boiled at 89-91", The crude iso- propylparatoluidine was purified by conversion into its nitrosamine, the nitrosamine being then reconverted into the base by treatment with tin and hydrogen chloride. Iso~ropy123aratoZyZnitrosanzine, (CH,),CH*N(NO)*C,H4-CH3, sepa- rates frum alcohol in beautiful, slightly yellowish crystals, melting at 58-59' (uncorr.). It is easily soluble in ether, benzene, alcohol, and glacial acetic acid, but insoluble in water.It cannot be distilled with steam. 100 grams of alcohol (984 per cent.) dissolve 65 grams of the iiitrosamine at 22". On combustion, 0.2598 gram of the substance gave 35 C.C.of nitrogen at 18" C. and 754 mm. bar. pressure corre- sponding to 15.89 per cent. nitrogen, the calculated percentage being 15-73. I n the conversion of the nitrosiLmine into isopropylparatoluidine by warming with tin and hydrogen chloride solution, a yield of only 60 per cent. of the theoretical amount was obtained, but we failed to improve this yield by other methods of effecting the conversion. Isopropylparatoluidine may also be pile pared from diazotoluene- toluide, C7H7*N3,*NHG7H7, an alcoholic Rolution of sodium ethylate, and isopropyl iodide by heating the mixture for five hours on the water-bath, distilling off the alcohol, pouring the solution into cold water, and decomposing the precipitate with hydrogen chloride ; but the yield in this case is not very good.Iso~rop1JZparatoZz~idine is a colourless oil, which slowly becomcs coloured. Its deizsity is 0.9226 gram per C.C. a t 20", 0.9209 a t 23", 0.9129 at 35", 0.8988 at 51", and 0.8937 at 56". The density at its boiling point, determined by Ramsay's method, was found in three experiments to be 0.7469, 0.7452, and 0.7477, the mean being 0,7466. This gives a moleculay specific volume of 199.57, whilst Bruhl's formula for specific volumes would give 199.50 as the calculated number. The index of refraction was kindly determined by Dr. A. H. Pison, of University College, to be as follows :- It boils a t 219" to 221" (nncorr.). Line. Wave-length. Index of refraction. Ha.. .............. 6562 1.5277 D ................ 5892 1.5322 Hp................ 4861 1.5473AND ISO-PROPLYPARATOLUIDIXE. 35 Calculating the molecular refractive energy from the values for the lines Ha and Ha, we obkain 81.4 instead of the theoretical number 79.3. fVorma1 ~so~ropyl23arntoZ~~id~~ae Oxalnte, (CloH,jN)2,H,C,04.-The base forms both a normal and an acid oxalate, but the latter being exceedingly soluble both in water and alcohol is not easily crystal- lised, whilst the former is 0nl-j- slightly soluble in cold water, and can be easily crystallised from dcohol. The normal oxalate crystallises from h o t absolute alcohol in colourless crystals melting at 129-130" (u2corr.). Three deter- minations of oxalic acid gave 23.02, 23.26, and 23.18 per cent. respectively (calculated 23-19>. The Salk is almost insoluble in cold water, but on warming it dissolves with partial separation of the base.100 grams of alcohol (9Sa per cent.) dissolve 4.76 grams at 17" and 5.76 grams at 22". Isopropylpas.atoli~idine Hydrochloride, C1,Hl5N,HCl.-This salt, which separates as colourless crystals, on passing hydrogen chloride into a, solution of the base in ether, crystallises from alcohol in large crystals of wax-like colour melting at 170-171". It is very easily soluble both in water and alcohol, slightly in cold benzene, and easily in boiling benzene, from which it separates in needles [Cl = lS.69 and 18.63 ; calc. 19-13]. The ferroc yanide, (C,, H15N)2,H4-E'eCyS, obtained by precipitation, is a white powder [Fe = 11.55 and 11.12; calc. 10.891. Xomzai P~o~~~aal.atolzt.idine.Normal propylparatoluidine was prepared by heating equimolecular weights of normal propyl iodide and paratohidine for two days in sealed tubes at 160"; the yield being 90 per cent. of the theoretical. The normal propyl iodide used was prepared fieom propyl alcohol, amorphous phosphorus, and iodine, and boiled at 101-103" (uncorr.). The normal propylparatolnidine was purified, like its isorneride, by conversion into its nitrosamine. NornzaZ Pro~yZpal.afolyZnits.osa?ni~c, CH,-CH,-CH,*N(NO)*C,H,*CH,, is an oil, not solidifying at -20'. On heating, it begins to decom- pose below 10CIc, giving off nitrous fumes. In converting it into normal propylparatoluidine, the yield is only 50 per cent., and the boiling point of the resulting base is not so sharp as that of its isomeride, so that some fractional distillation is necessary.Normal Propylparatolicidine is a colourless oil, boiling at 230-233", and does not become much coloured even on standing for a long time. Its solubility is 0.9243 gram per C.C. at 20", 0.9296 a t 23", 0.9172 at 35") and 0.9053 at 51". The density at the boiling point D 23 6 ON NORNAL AND ISO-PROPTLPARATOLUIDINE. was found in four determinations to be 0.7554, 0.7546, 0.7533, and 0.7539, the mean being 0.7543. This gives a molecular specific volume 197.53 (theory 199.50). The index of refraction was kindly determined by Dr. Fison to be as follows :- Ha.. ................ 1.5306 D ................... 1-5367 H g .................. 1.5495 The molecular refractive energy ( 'L- ')A$ calculated from the values for Ha and H p is 82.5.Oxnlates qf Normal P~o~y7pa~atoZzcidine.-Normal propylparatolui- dine forms both normal and acid oxalates ; but the normal oxalate, when in solution, easily decomposes into the acid oxalate and the base, and it is, therefore, difficult to obtain i t in a, crystalline state. The acid oxalate, ( C,oH,,N),C2H,0i, crystallises from alcohol, and melts at 172-173" with decomposition. The percentage of oxalic acid was found t o be 37.86 and 37.644 (calculated 37.65). The acid oxalate is only slightly solu'ule in cold water and alcohol, but easily dissolves on warming. 100 grams of alcohol (98$ per cent.) dissolve 1.4 grams at 21'. On mixing equimolecular proportions of the base and oxalic acid, both in alcoholic solution, a precipitate of the acid oxalate is obtained, but the filtrate, when left to evaporate spontaneously, deposits white powdery crystals of the normal salt (C~oH~~N)2,C,H204 [Percentage of oxalic acid found: 23.25 and 23.08; calc. 23.191.The normal oxalat'e can also be obtained by adding a large excess of the base to a cold alcoholic solution of the acid oxalate, when crystals of the normal salt often separate a t once, and further quantities may be obtained by spontaneous evaporation. The normal oxalate of normal propylparatoluidine melts at 116-117", and is more soluble both in water and in alcohol than the acid salt. Its aqueous solution when warmed becomes milky, from separation of the base, but becomes clear again on cooling. If the solution is heated to boiling, i t deposits, on cooling, the acid oxalate only.Normal and iso-propylparatoluidines may be separated through the difference in the solubility and stability of their oxalates. If a mixture of the two bases be gradually added to an aqueous solution of oxalic acid, sufficient t o form acid oxalates, a crystalline precipitate of the acid oxalate of normal propylparatoluidine is formed. On evapo- rating the filtrate, and allowing it to cool, more of this salt separates, but after repeating this process several times distinct crystals of t h eYOUNG : THE SPECIFIC VOLUMES OF LIQUIDS, ETC. 37 osalate of ieopropylparatoluidine begin t,o appear. On adding potash t o the mother liquor at this point, almost pure isopropylparatoluidine is liberated. The hydrochlovide of normal propylparatoluidine, CIoHl5N,HC1, crptallises from boiling benzene in needles melting at 150-151" [Cl = 18.95 per cent. ; calc. 19.13 pcr sent.]. It is very soluble in -\?;nter and alcohol, slightly soluble in cold benzene, easily soluble in boiling benzene. The f ewocyanide of normal propylparatoluidine, ( CIOH,,N),,H6FeCy6, is a white solid, turning blue on exposwe to light [Fe = 11.09 per cent. ; calc. 10.891.

ISSN:0368-1645    

DOI:10.1039/CT8915900033

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

YOUNG : THE SPECIFIC VOLUMES OF LIQUIDS, ETC. 37 IV.-A New MctJaod of Detemniwhzg the Spci$c ?Tolumes of L i q u i d s and of their X n t w a t e d Yapours. By SYDNEY YOUSG, D.Sc., Professor of Chemistry, University College, Bristol. IF a closed graduated tube, containing a known volume of liquid at a given low temperature to, be heated to some higher temperature To, the liquid will expand, but the apparent expansion will be smaller than the real, on account of the evaporation of a portion of the liquid. If the density of the saturated vapour, or the ratio of the specific volume of the vapour to that of the liquid at To is known, the necessary correction may be applied, but at temperatui?es above the ordinary boiling point of the liquid this is usually not tlie case. Suppose now that by some suitable arrangement one portion ca of the tube cd (p. 38) can be heated to To, the remainder of the tube, ad, being kept at a constant low temperature fo, and tlhat by moving the tube, or the heating apparatus, a greater length ca' of the tube can subsequently be heated t o To, then we shall have a second method of determining the apparent expansion of the liquid. For a known volume of t h e liquid aa' at to has been heated to TO, and has expanded from b to b'.But in this case the space above the liquid is always filled' with saturated vapour, and since the rolume cb' is less than cb, the apparent expansion is greater than the real, f o r the vapour originally occupying the volume bb' has riow condensed. Here again, the ratio of the specific volume of the saturated vapour to that of the liquid at To being usually unknown, i t is impossible t o calculate the true expansion from to to To.But since by each method we have the38 YOUNG: THE SPECIFIC VOLUMES OF LIQUIDS Rame two unknown values-the true volume of the liquid and the ratio of the specific volume of the vapour to that of the liquid-we can obtain two equations from the experimental data, from which both values may be calculated. Let V, be the true volume of the liquid at To, and r the ratio of the specific volume of saturated vapour t o that of liquid at To. In the first experiment, when the whole tube is heated to To, let V’, be the apparent volume of the liquid, and V, the volume of saturated vapour. Then the volume of liquid at To, formed by the condensation of the saturated vnpour V,, would be VJr, and the true volume of liquid at To = v c v, = V‘, + -.r I n the second experiment, let Vt be the total volume of liquid at f, Va the volume of liquid between a and a’, and VB the apparent expansion from b t o b’. Then, since V, volumes of liquid at to expand so as to occupy the volume V, f VB at To, the total volume of liquid Vt would, under the same conditions, occupy the volume But in conse- V T’, (V, -j VJ.AND OF THEIR SATURATED VAPOURS. 39 quence of the expansion a certain amount of the saturated vapour has condensed, and the error due to condensation-calculated for the total Vt VR volume of liquid-will be - . --. Therefore, the true volume of v, ?' liquid at To will be From these two equations we have and the ratio of the specific volume of saturated vapour to that of liquid at To will be IT, v, - VIT' Lastly, the specific volume (volume of 1 gram) of liquid at To r = will be VT x Sr s, = - Vt ' where St is the volume of 1 gram at to ; and the specific volume of the saturated vapour st To will be ST = r x ST. It is of course impossible to heat the whole of one portion of a, tube strongly, and to keep the whole of the remainder of the tube a t a low temperature; there must be an intermediate portion, one extremity of which is at the higher temperature, the other at the lower, the temperature falling gradually from one extremity to the other.If, however, in both stages of the second experiment there is a similar gradation of temperature, though of course in different parts of the tube, the results will not be affected provided that the tube is of even bore.I have succeeded in devising an apparatus by which the specific volumes of liquids and saturated vapours may be determined by the method described, and as the metlt,od i s applicable to liquids which ccttack mercury, and may be epnployed through a wide range of tempera- tures, it seems desirable to give a detaiied account of it. A piece of barometer tubing, of very even bore and of about 60 cm. length, is closed at the blowpipe at d (Fig. 2, p. 40), about 20 cm. from one end, the closed part being carefully rounded. The portion of the tube de serves as a handle, and the end e may conveniently be d o se d .40 YOUNG: THE SPECIFIC VOLUMES OF LIQUIDS The tube from d to c is then graduated in millimetres, and calibrated in the usual manner by weighing with mercuryr Fig.2. e d C Cc > The end c is then sealed to the apparatus shown in Fig. 3, and the whole apparatus is thoroughly dried by repeatedly exhausting and allowing dry air t o enter. FIG. 3. The freshly distilled liquid is then admitted iuto the apparatus at g, either by means of a fine funnel, or, if the liquid is hygroscopic, by means of a siphon arrangement such as that described by Thorpe (Trans., 1880, 37, ad), until the wide protuberance f is about one- third filled. A piece of thick-walled indiarubber tubing, provided with a screw clip, is then passed over g, and the apparatus is con- nected with a pump and exhausted. The clip is then closed, the apparatus removed from the pump, and the liquid in the tube cd made t o boil vigorously for some time, so as to completely remove air adhering to the walls of the tube.(The narrow tube h, drawnAND OF THEIR SATURATED VAPOURS. 41 out and bent at the end, prevents the projection of the liquid against the indiarubber.) Lastly, the liquid is allowed t o fill the tube corn- pletely, and is then boiled from above downwards until only the iaequired amount remains in the tube, when the apparatus is tilted, s o that the greater part of the liquid above h flows intof. The tube is then at once sealed at c, the glass being allowed t o fall together, so as to withstand a high internal pressure. The volume of liquid is then nieasnred, either at 0" or with the tabe surrounded by running water of known temperature. The total volume of the tube, which is as yet unknown, is easily ascertained by inverting the tube, so that all the liquid flows to thc other end, and taking a second reading.The sum of the two readings gives the total volnme, but as the tube was calibrated with mercury, which has a convex meniscus, while that of the liquid is concave, the first reading must be corrected for this reversal of meniscus. When the tube is inverted, the concave meniscus of the liquid corresponds in position with the convex meniscus of mercury during calibration, and no correction is required. AB is a jacketing tube, containing a pure liquid which is t o be boiled under The arrangement for heating the tube is shown in Fig. 4.42 YOUNG: THE SPECIFIC VOLUNES OF LIQUIDS known pressures. The lower end of the jacketing tube is narrow, and is provided with a piece of indiarubber tubing, C, through which the volume tube cd passes.A current of cold water passes through the tube D, and keeps the loxer part of the volume tube at a constant temperature, which is measured by the thermometers GG’. If the indiarubber tube C has been kept under water for several hours before it is placed on the jacketing tube, the volume tube may easily be pushed up through it ; but, notwithstanding the reduced pressure in the jacketing tube, no water passes up between the indiarnhber and the volume tube. A ring of lead, L, is placed above the indiarubber cork I, so that the jacketing tnbe D may always be pushed up to exactly the same height.The position of the volume tube in the jacketing tube is shown by a horizontal line E, etched on the narrow part of the jacketing tube. The scale divisions on the volume tube corresponding to this etched line give the readings a and a’ (Fig. 1, p. 38). The jacketing tube is protected from drainghts by the outer tube HH, the space between A and H at the top being closed by a ring of asbestos cai=dboard. The experiment is begun with the volume tube in the position shown in the diagram. The liquid in B is made to boil, and when the vaponr has reached the top of the jacketing tube, and the pressure has been regulated to give the desired temperature, the volume tube is pushed up until the liquid in it is about 25 mm. above the level of the liquid F.The reading a may be taken at once, but tIhe height b of the liquid in the volume tube does not become constant until the liquid P (Fig. 4, p. 41), which has been cooled to some extent by pushing up the cold tube, has regained its original temperature. From 15 to 20 minutes are required before the reading of b becomes quit’e constant, but it is advisable to take readings every few minutes until constancy has been attained. The volume tube is now pushed LIP again until ihe bottom of the tube d is abowt 10 or 20 mm. below E, when the readings a and b’ are taken in the same manner as before. Lastly, the volunie tube is pushed up until d is about 25 mni. above F, when, of course, the whole of the liquid is heated, and the rending V’ is taken. In this case, the reading becomes constant after three or four minutes.The expansion of the liquid at low temperatures having been determined in the ordinary way, the volume Vt at the temperature t of the flowing water may be calculated or read from a curve, and we have now all the data required for calculating the specific volumes of the liquid and saturated vapoL1-r at To.AND O F THEIR SATURATED VAPOURS. 43 It is necessai-y, however, to apply the following correctioiis :- 1. The apparent volume of liquid at the ordinary temperature 01- 0" is slightly too small, as a certain quantity of the substance is present in the form of satumted vapour. The correction, which is very small, may be made on the assumption that the density of the satitrated vaponr is normal. 2. The expansion of the glass must be allowed for in the calculn- tion of VB, VrT, and V,. It is generally too small t o affect the value of V,.I n order to test the accuracy of the method, as regards the deter- mination of the specific volumes of liquids, experiments were made with benzene and carbon tetrachloride, for which substances accurate d a h have been obtained by the method employed in the investiga- tions of the benzene derivatives (Trans., 1889, 55, 486). In the experiments with carbon tetrachloride, however, aird in the earlier ones with benzene, the water jacket was not employed. A com- parison of the two series of determinations with benzene shows that more accurate results are obtained by the addition of the water jacket :- The results by the old and new methods are given in the following tables :- CCL; Temperature.100 200 210 220 230 250 260 Tolume of 1 gram liquid. Old method from curye. 0 '6972 0 *8408 0 '8637 0 -31 99 0 *999s 1 -0390 (J *8898 0 .GO6 1 0 -8418 0-8664 0 *sag9 0 -9219 1 -0029 1 -0CGO Difference per cent. -0 -16 + 0 '18 + 0 -30 + 0 *01 +0*24! + 0 -48 + 0 *6644 YOUNQ : THE SPECIFIC VOLUMES OF LIQUIDS Old method from curve. Temperature. Nem method. 100 130 160 190 220 24G 260 160 170 240 260 Eenzent: (witJLout TVafey Jackst). Volume of 1 gram liquid. I 1 -2616 1,3214 1 -3918 1 -4797 1 -5973 1 '7092 1 -8'7'70 L -2607 1 -3191 1.3877 1 *4815 1 -6006 1 9'174 1 W345 Beizaene (with TVater Jacket). 1 *3918 1 *4186 1 TO92 1-87'70 1 -3931 1 -4202 1 *ti123 1 -8809 Difference per cent. - 0 -07 -0 -17 -0 -29 +0-12 f 0 '21 -+ 0 -48 i- 0.40 + 0 '09 +0*11 +Om18 -t 0 -21 It will be seen that in the four determinations with the water jacket the greatest error is only 0.21 per cent., and that even without the water jacket the errors do not exceed 0.3 per cent., except at the highest temperatures.The chief value of the method depends on the fact that it can bc employed for the determination of the expansion of liquids such as nitrogen peroxide, bromine, 01' chlorine compounds which attack mercui-y. Xpec$c Volumes of Saturated Vapozw. The ratio of the specific volume of saturated vapour to that of liquid at To is given by the equation where V, is the volume of saturated vapour in the tube, V, the true volume of liquid, supposing all the rapour to be condensed, and V', the observed volume of liquid.It is clear that accurate results can only be obtained when the value V, - V', is fairly large, otherwise a, small error in either V, or V', would mean a relatively very much larger error iii their difference, and therefore in the value of r.AKD O F THEIR SATURATED VAPOURS. 45 Tempera- ture. ---- 160 170 180 190 200 2 10 220 230 240 250 260 270 280 -45 With a tube of the form employed, the results are sufficiently accurate only at high temperatures, at which the density of the saturated vapour is considerable. At low teniperatures the volume of the saturated vapour relatively to that of the liquid should be greatly increased. Of the three values V,, V'T, and VT, the two first are obtained by direct reading, and may therefore be considered as very accurately determined.On the other hand, the calculation of V, depends on a nniiiber of readings, and this value is therefore subject to greateia chalices of error. I f , therefore, better values of V, than those afforded by the new method are available, it is better to make use of them. Now the specific volumes of liquids, as determined by the old method (Phil. Trans., 178, 573, are calculated from a single reading in each case, and the values of V, can be calculated directly from them. I n the case, therefore, of substances which do not attack mercury, the best results mill be obtained by determining the specific volumes of the liquid by the old method, and the values V, a n d VIT by the new. There is also the great advantage that the time required for each determination of V', and V, is 1-ery small, for as the whole of the liquid is heated, the position of the voli-r.me tube in the jacketing tube does not require t o be altered during the experiments.I have determined the values of VfT and V, for carbon tetra- chloride in this manner at other temperatures in addition t o those given in the previous tables, and though I have as yet no means of testing the accuracy of the results, i t may be worth while to give d l those obtained at high temperatures. QC. . 0.8592 0 *8534 0 * 8479 0 *8425 0 -8369 0 -8313 0 '8259 0 %206 0 -815'7 0.8116 0 *8094 0 -8120 0 %400 Car4 ow Tetrcrch 1 oyide. QT. 1 -- 0 *5633 0 -5743 0.5864 0 -5998 0 -6149 0 -6316 0 -6507 0 -6'727 0 *698'7 0 5'311 0 '7743 0 -8395 0.9675 V'T. 0 -5402 0-5464 0 *5523 0 -5581 0 -5640 0.5699 0 '5'758 0.5814 0 '5866 0 '5911 0.5936 0 -5914 0 *5638 YT. 37 *00 30 -50 24 *90 20.20 16 '40 13 -50 11 .OO 8.99 7 -28 5 -80 4 '48 3 '27 2 *08 Voluine of 1 gram P a t urated vapour. 28 *50 24-00 19 * 90 16 *60 13 -80 11 -60 9 -81 8 '27 6 -95 5 *80 4 -74 3 -76 2 -7546 O’SULLIVAN AND TOMPSON : THE ESTIMATION Thz last two values of VT are somewhat uncertain, as carbon tetra chloride attacks mercury at high temperatures, and the values of VT were calculst,ed from the results by the old method. I hope before long to be able t o obtain some deterniinations of the volumes of a gram of the saturated vapours of the haloid derivatives of benzene, in order t o find whether the generalisation of Van der Wads holds good for these snbstances in the state of saturated vapour as well as in the liquid state.

ISSN:0368-1645    

DOI:10.1039/CT8915900037

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

46 O’SULLIVAN AND TOMPSON : THE ESTIMATION V.--The Estimation of Cane-sugar. By C. ~’SULLIVAS, F.R.S., and FEEDRRTC W. TOYPSON. THE accurate estimation of sucrose in the presence of other carbo- hydrates has always been attended with considerable difficulty ; indeed, in many cases, i t was not found possible until Mjeldahl, in 1881 ublished a paper on the carbohydrates of malt (JfeddeZeZser, 1881, . h i ) . Some time afterwards, in a paper by one of us on the same subject, a method of estimating cane-sugar was given drnost identical with his (Trans.: 1886,49,58). In both cases very accurate results were obtained, and, as the latter paper was published in ignorance of Kjeldahl’s work, it may be regarded as an independent confirmation of it. It is obvious that in solutions such as those obtained from malt, the usual method of estiniating cane-sugar with acid is inapplicable on account of the action of the acid on the othcr carbohydrates.Indeed, this is the case in nearly all solutions obtained from natural sources. This difficulty was overcome by the use of the enzyme, invertase, arid it was eniploycd either in the form of a soluble preparation, or, in the raw state, as brewers’ yeast, together with sufficient thymol to prevent fermentation and growth of yeast. By this nieans the cane-sugar was inverted without any other substance present beiiig altered, and the results thus obtained were perfectly trustworthy. The decrease in optical activity, and the increase i l k cupric reducing power, each formed a measure of the amount of sucrose originally present in the solution.Very concordaiit results were obtained. The estimation of cane-sugar by means of invertase is without doubt a perfectly satisfactory process. The only disadvantage consists in the difficulty of preparing the invertase. Until the recent publica- tion of our paper on invertase (Trans., 1890, 57, 834), this objectioii ’ P‘,,,OF CAKE-SUGAR. 47 vas practically fatal? and it still forms a great drawback to the .universal application of the process, as i t takes at least three weeks t o prepare invertase by our method.* The use of yeast as the hydrolyst has hitherto been held t o require the presence of some such substance as thyniol, to prevent ferments- tion, and this method has not generally been considered to be so i*eliabIe as the former one.It is the puqose of the present paper t o show that the process known commercially as " Tompson's Inversion Process " is perfectly applicable to the estimation of cane-sugar. In this process, ordinary brewers' yeast is employed as the hydrolytic agent without the addition of anything else.' W e shall show that w e have in this rriethod a simple aiid convenient means of estimating cane-sugar independently of other substances in solution, and that she results obtained are accurate and trustworthy. Our procedure is as follows :-The aolntion containiiig the cane- sugar must be approximately neutral (certainly not alkaline), and if the presence of any enzyme is suspected, the temperature should be momentarily raised t o SO" t o destroy it.The optical activity at 15.5" and the cupric reducing power of the solution are determioed,? and then 50 C.C. of it are poured into a beaker and raised to a temperature of 55" in a constant temperature bath. Some ordiuary brewers' yenst, pressed in a towel, is iiow taken. The weight of the pressed yeast should be about l/lOth of the total amount of sugar t o be inverted.: It is thrown into the hot solution, and the whole yent1-y stirred until mixture is complete. The solution is left, for 4 hours in the water-bath: at the end of this time it is cooled t o 1.;*5", a little freshly precipitated aluiniiiium hydrate added to * We take this opportimity of making known the means we have now adopted for keeping a prsparation of invertase as a hydrolytic agent. We have, in oui- fornier paper, given details of tlie preparation of the solution called yeaat liquor.To this we add alcohol uiitil tlie whole conbains about 10-12 per cent. absolute alcohol. Tlic mixtare is a~lowecl to stand it few days, and then tlie cleay solution is filtered off. This solution is kept in a stoppered bottle, and it retains its invert- ing power indefinitely. It may either be nsed in. its undtered state or tho in- veytase may be thrown out of solution by the addition of 3 or 4 times its own bulk of alcohol, and tlie sympy precipitate, which immediately falls out, redissolved in water. We thus get, at a few minutes' notice, a fairly pure, and very strong solution of invertase. -j- It is not necessary t o determine both the optical activity and the cupric re- ducing power, as either factor by itself is sufficient.The o p t i d activity will be found to be the inore convenient, :md, iTe think, the more accurate of the two, unless t h e solution is highly coloured. $ Brewers' yeast varies considerably in inverting power, but we t<hink this ainount is amplc in most cases. The yeast need not necessarily be Presh, as i t does not easily lose its power.48 O'SULLIVAN AND TOXPSON : THE ESTIMATION facilitate filtration (this is not always necessary), and the whole made up to 100 C.C. A portion of this solntion is filtered, and the optical activity observed. The solution is then left in the cold until the next day, when another observation is taken in order to prove that inversion is complete. The cupric reducing power is also esti- mated.The method of calculating the results is the same as when in- vertase is used. F ~ o m the optical activity, the cane-sugar may be calculated as follows :- The following f o r m u l ~ will be found useful. cc = the number of divisions indicated by the polarimeter scale for a' = the same factor in the inverted solution. nz = the number of divisions of tlie polarimeter scale which 200 mm. of a solution containing 1 gram of cane-sugar per 100 C.C. alters on being inverted. I n the case of the Soleil-Ventxke-Scheibler polarimeter which we use, 1 gram of cane-sugar in 100 C.C. indicates + 3.84 div., whereas nfteia inversion it gives - 1.34 dir. Therefore for our experiments rrz = 5.18. P = the weight of cane-sugar present in 100 C.C. of the original solution .From the cupric reducing pozuer we calculate the cane-sugar as 200 mm. of the original solution. f 0110 FVS :- W G = the weight of 100 C.C. of the original solution. (3' = the same factor for the inverted solution. Allowance must, of course, be made here both for dilution and for the 5 per cent. increase of the inverted sugar, but the latter number is so small that it need not be calculated accurately. 20 = the weight of original solution used for the estimation. w' = the same factor for the inverted solution. 7c = the weight of cupric oxide reduced by w. k' - the same factor for z d e p = the weight of cane-sugar present in 100 C.C. of the original It is needless to remark that the values P a n d p should be identical within the limits of error of manipulation.It will be seen from the description we have given that this method of estimating cane-sugar is quick and! simple; it only remains for solut'ion.OF CANE-SUGAR. 49 Results calculated on us to prove its accuracy. I n the following experiments, we ha,ve compared it side by side with estimations made with a preparation of invertase; the accuracy of the latter method is, we believe, un- disputed. Exp. 1.-A blank experiment to test whether the yeast itself imparts any optical activity to the solution. 1 gram pressed yeast was heated in 50 C.C. water to 55" for 4 hours. It was then filtered off by the aid of a little aluminium hydrate. The optical activity of the solution was 0.0 to -0.2 div. in 200 mm. It is obvious that tho optical activity due to the yeast may be neglected.Exp. IT.-Estimation of cane-sugar in a hot water extract of malt. Original solution. Sp. gr., 1079.7. Optical activity after heating t o 80", +67-4 div. in 100 mm. I( of the solution diluted to twice its original bulk, 1.270 grams solution gave 0.1159 gram copper oxide. Inversion was performed in 3 beakers ; each contained 50 C.C. of the solution, and was treated exactly as we have described. Beaker 1.-0*1 gram pressed yeast was employed. Optical activity after 4 hours +63*5 div., next day +63.2 div. in 200 mm. K, 1.320 grams solution gave 0.1405 gram copper oxide. Beaker 2.-A solution of prepared invertase was used. OpticaI activity after 4 hours +63.2 div., next day + 6 3 2 div. in 200 mm. Beaker 3.-2.57'0 grams pure cane-sugar were added, and 0.2 gram yeast was employed.Optical activity after 4 hours +60*4 div., next day +60*0 div. in 200 mm. K, 1.274 grams solution gave 0.2020 gram copper oxide. After making the calculations in the manner we hare described, the results may 'be tabulated as follows :- Grams cane-sugar indicated by the Optical activity. - TABLE I.-l'he Estimation of Cane-sugar i i ~ the Hot-water Extract of Mcclt. 100 C.C. of the solution Amount added t o the solution 7 9 9 9 -I--I- 1'62 1-36 1 -62 2 -62 2 *34 - Yeast none j I n E t e 1 none 2 *530 It will be seen from this table that whilst the results calculated from the decrease of optical activity are perfectly satisfactory, those obtained from the increase in the cupric reducing power are not so VOL. LIX. E50 THE ESTIMATION OF CAKE-SUGAR.Cane-sugar indicated by the good. TEia may be accounted for by the high reducing power of the original solution. Exp. 111.-Some treacle was dissolved i n water with a little loaf sugar ; the cane-sugar was then eskiiiiated as follows :- Original solution. Sp. gr. 1054.2. Optical activity +18.9 div. in 100 mm. Beaker 1.-A solution of prepared invertase was used. Optical :tctivity after 4 hours -6.1 div., next day -6.4 div. in 200 mm. K, 1.309 grams solution gave 0.1800 gvam copper oxide. Beaker 2.-0*4 gram pressed yeast mas employed. Optical activity after 4 hours -6.4 div., next day -6.7 div. in 200 mm. I(, 1.357 grams solution gave 0.186 gram copper oxide. K, 2.312 grams solution gave 0,1124 gram copper oxide. We have tabulated the results.Agent employed. Be*;ker. TABLE II.-TJLe Estirnation of CYame-sugaj* in a Solution of Treacle, showing granzs of Sugar in 100 C.C. of t h Solution. Cane-sugar indicated by the optical activity. I I The agreement between these four results is remarkable. Ezp. 1V.-Some apples were finely divided and boiled in water. The solution was filtered off, arid the cane-sugar estimated. Original solution. Sp. gr. 1.024. Optical activity -11.3 div. in 200 mm. Beaker 2.-A solution of prepared invert'ase was used. Optical activity t,he next day -7.2 div. in 200 mni. Beaker 2.-0.1 gram yeast was used. Optical activity the next day -7.4 div. in 200 mm. TABLE IIJ.-Tlie Estimation of CnrLe-sugnr in, a Solution of Apple- jwice, ::howi,ng grains of Sugay i n 100 C.C. of the Solution. Tnvertsse 0 -60 Sea& 0 -67RICHARDSON: ACTION O F LIGHT ON PURE ETHER, ETC. 51 In this case the solution was too dilute to give perfectly accurate results, and, moreover, it was rather opalescent and difficult to see through. The results of these experiments agree so well together, that no doubt remains as to the accuracy of the process. We may remark that these experiments were not picked out on account of the good results obtained, but were done by theniselves specially t o test the trustworthiness of the process. I n conclusion, we do not hesitate t o say that the method we have described furnishes a simple and accurate means of estimating sucrose in all solutions.

ISSN:0368-1645    

DOI:10.1039/CT8915900046

出版商:RSC    

年代:1891

数据来源: RSC

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RICHARDSON: ACTION O F LIGHT ON PURE ETHER, ETC. 51 TTI.-Action of Light on Pure Ether i?z Presence of Moist Oxygen.. By A. RICHARDSON, PhD. THE formation of an oxidising body in ether which has been exposed' to the influence o€ light and air, was first, observed by Schobein (JOUY. Chenz. Xoc., 4, 134), a i d subscqueiitly this was identified with hydrogen peroxide, first by Dunstan and Uymond (Pharm. J., 17, 841), and afterwards by Berthelot (Compt. Tend., 108, 543) ; and also by Poleclr and Thumel (Ber., 22, 2863)-and myself (PYOC. Chem. rs'oc., 1889, 134). Recently, however, Dunstan and Dymond have published a paper (Trans., 1890, 57, 574), in which they state that pure ether is not acted on by light when exposed in a moist atmo- sphere containing oxygen, and they consider that the formatiori of the peroxide is due to impurities containeci in the liquid.I n the paper above referred to, an abstract o ~ l y of which wits published (Proc. Chenz. SOC., 1889, 134), Dunstan and Dymond discuss my o w n experi- ments on the subject ; tlhe ether used in these experiments was ob- tained from so-called pure ether (prepared from rectified spirits) ; it was repeatedly shaken with water until the last traces of alcohol had been removed, then dried over cslciiim chloride, and repeatedly dis- tilled from sodium until the metal was no longer acted on. Dunstan and Dymond, however, not having seen the original paper, consider that the means adopted to purify the ether used by me, as well as hy other observers, were insufficient t o preclnde the possibility of the formation of hydrogen peroxide from impurities contained in the ether, rather than from the ether itself.I have, therefore, repeated my former experiments, using ether obtained from different sources, and purified by some of the methods suggested by thcru. E 252 RICHARDSON: L u x I o N OF L~GHT ON PURE ETHER Experiments with Corn?nercial Ether. Commercially pure ether was taken, and all the alcohol removed by shaking about 30 timee with water, the process being r+epeated iintil the washings failed t o give the iodoforin reaction. The ether was then shaken with a 4 per cent. solution of potassium dichro- mate acidified with sulphuric acid : after washing with water, it was treated with a solution of sodium hydrogen sulphite, shaken with potassium hydrate, and, lastly, washed with water and distilled ; before exposure to light, the ether so prepared was without action on potassium iodide.Two quantities of this ether, of about 100 C.C. each, were exposed to light in bottles of colourless glass, containing also pure oxygen and water. After 11 days (July 13-24), the ether wqs tested with a solution of potassium iodide, to which it imparted zt deep yellow coloration; shaken with a solution of potassium di- chromate, the ether was coloured blue, thus proving the presence of hydrogen peroxide. Dunstan and Dymond, on the other hand, found that even methylated ether which had been purified in the manner above described was not affected by light, even after an ex- posure of five months. Expeyiments with Ether pp-epnred f r o m Pure Alcohol and Pure 8ulp l~uric Acid.The ether prepared from the pure reagents was first shaken re- peatedly with a solution of potassium hydrate and then with water till the washings failed to give the iodoform reaction. The ether so purified was treated as follows :- (1.) About 200 C.C. of the pure substance was shaken with its own 1-olume of potassium dichromate, every precaution being taken t o follow exactly the method described by Dnnstan and Dymond, and was distilled before being used. Samples of this ether, placed i n bottles together with water and oxygen, were exposed to the influ- ence of sunlight in a glass tank containing water, the temperature of which varied between 13.3" and 26.1". In one experiment, air was substituted for oxygen above the liquid, the conditions being other- wise the same.Another bottle, containing ether and moist oxygen, was protected from the light by a covering of tin-foil, and was placed with the others in the tank, so that the heating effects were in all cases the same. After an exposure t o light of 16 days (August 1-19), ihe contents of the bottles were examined ; the ether which had been exposed to light gave witlh potassium iodide and with a solution of titanic acid it deep yellow colour, and potassium dichromate colouredIN PRESENCE OF MOIST OXYGEN. 53 the ether blue, whilst tlie ether which had been protected from the light was without action on these reagents. (2.) The second method of purification consisted in the treatment of the ether with hydriodk acid; by this, as b y the dichromate method, Dunstan and Dymond state that they mere enabled t o purify methylated ether so completely that after five months exposure to light it, was wit,hout action on potassium iodide solution.A portioc of the ether (about 100 c.c.) prepared from pure materials was, there- fore, shaken repeatedly with about its own volunie of a 3-4 per cent. Folution of hydriodic acid, t'he method described by Dunstan and Dyinond being again carefully followed. The ether, after distillation, was exposed to light i n presence of moist oxygen, the bottle, as before, being imrnersed in water, the temperature of which ranged between 13.3" and 23". A.fter five days exposure (July 24-29), the ether was tested with a solution of potassium iodide, and gave a, yellow colour, which grew darker on standing; it also imparted a yellow colour to a solution of titanic acid.Bther exposctl under the same conditions, except that it was protected from the light, gave no reaction with these reagents. ( 3 . ) The ether from the last experiments, amounting to about, 200 c.c., containing hydrogen peroxide, was collected and again shaken with potassium dichromate, the process being repeated five or six times; the ether, which was colourecl blue, was washed with sodium hydrogen sulphite and with potassium hydrate as before : after distillation, it was exposed with oxygen and water to a north light, so as to avoid direct sunlight, the temperature varying from 10" to 17.7'. Another sample was conipletely protected from the light, but otherwise exposed to similar conditions.After seven days (August 20-27), the ether was tested; that which had been ex- posed to light gave a, yellow coloration 130th with potassium oxide and with titanic acid, whilst these reagents were not acted on by the ether which had been protected from the light. Experiments with Ethel- p e p a r e d froin CL Second Xaiqde of Pure Alcolzol. It was thought desirable to prepare a fresh quantity of ether from a new sample of absolute alcohol, which before use was allowed to stand over calcium oxide for 12 hours and then distilled ; the ether obtained by the action of pure sulphuric acid on this alcohol was, as in the preceding experiment, shaken with potash and with water till all alcohol had been removed ; it was then treated with potassium dichromate, dried over calcium chloride, and lastly over metallic sodium.The boiling point of this ether, amounting to 300 c.c., was54 RICHARDSON: ACTION OF LIGIIT ON PURE ETHER determined with a thermometer graduated to 0.1" ; it was constant throughout at 346' under a pressure of 760 Em. corrected to Oo. This result is identical with that found by Perkin and by Ramsay and Young, whilst the ether used by DunGtan and Dyrnond boiled at 35", a somewhat higher tlsmperature. A portion of this ether was exposed to a north light as in the preceding experiments, the tem- perature varying between '7.2" and 15.5". After seven days expo- sure (September 29-October 6), the ether liberated iodine from potassiuni iodide, and a titanic acid solution was coloured yellow.An experiment was next made in which pure ether was exposed to the action of light at a low temperature, so that the heating effects might, as far as possible, be eliminated ; this was done by surround- ing the bottle containing ether and oxygen with water, which by the addition o f ice was never allowed to rise above 2". After exposure to light for four days, the ether was found to contain hydrogen per- oxide. It appears, therefoi-e, that the formation of this substance is brought about by light aloue, independently of any heating effects. From these experiments it will be seen that hydrogen peroxide was formed when ether, water, and oxygen were together exposed to light when the specimens of ether were prepared-(1) from the corn- mercial " pure '' product subscquently treated with potassium di- chromate ; (2) from pure alcohol and pure sulphuric acid, the prz- duct being afterwai-ds treated with potassium dicliromate or hydriodic acid; (3) from pure ether as in (2), in which hydrogen peroxide had been formed, but had been removed by further agitation with potassium dichromate ; (4) from an entirely different specimen of pure alcohol and pure sulphuric acid, the ether being further purified with potassium dichromate, its purity being confirmed by the agree- ment of its boiling point with that obtained by other observers.Dunstan and Dymoiicl state that the formation of hydrogen per- oxide in ether is the result of some unknown impurity, which can, however, be removed from even the inethylated product by treatment with potassium dichromate ; it might, thcrefore, be supposed t h a t ether prepared with the utmost care from pure materials would after such treatment be freed from this substance, but, as has been shown, hydrogen peroxide is still formed in such a liquid after expo- sure to light, provided oxygen and water are present.Even on the supposition that the impui-ity escaped decomposition in the first instance, a second application of pot aasium dichroniate should be sufficient to completely rid the ether of this body, but again it is found that hydrogen peroxide is formed in the ether after a few days exposure to light. In 110 case have I been able to obtain a specimen of ether in whichIN PBESENCE OF MOIST OXYGEN. 55 hydrogen peroxidc is not formed after short exposure to light under tbhe conditions above mentioned ; and it, would seem that the explanation of the discordant results obtained by Dunstan and Dymond and by myself is to be found, not in the supposition that my ether was impure, but in the conditions under which the ether was exposed to light in the two cases.I n the first place, one is led to enquire whether Dullstan and Dymond really had any oxygen above the ether in the bottle during cxposure to light. For, although they describe minntely the nature and size of the bottles and the quantities of ether used, no allusion is made in their published paper to any precautions they may have taken to secure an atmosphere of oxygen or air in the space above the liquid. When ether is poured into a bottle, the vapour is evolved in such laiege quantities that the air is, to a great extent,, expelled, and it is therefore open to doubt whether, if special precautions were not taken, sufficient oxygen was really present.I n one experiment made with the object of ascertaining whether oxygen has any action on ether (Trans., 1890, 57, 577), these ob- servers passed 200 litres of oxygen in the course of two days through ether heated nearly to its boiling point, and they remark that, although the ether was exposed t o light during this period, no hydrogen peroxide was formed; two days exposure t o light in a London laboratory would, however, hardly be sufficient to bring about the formation of a recopisable quantity of peroxide, even when oxygen is used.In my own experiments, oxygen or air was in every case passed into the bottles immediately after the ether had been added; the stoppers were then inseyted, and the bottles exposed to light in an inverted position, so that no gas could escape without first expelling thc whole of the liquid. Again, it is to be noticed that Dunstan and DTmond used bottles of faintly greenish glass, which absorbs, to a considerable extent, the rays most influential in bringing about the formation of hydrogen peroxidc. Lastly, it does not appear that they distilled the ether after treatment with potassium dichromate and sodium hydrogen sulphite, o r after purification with hydriodk acid and sodium thiosnlphate ; traces of any of these reagents would be sufficient to decompose the minute quantities of hydrogen per- oxide formed under the most favourable conditions.Oiie is, there- €ore, led to suppose that the results obtained by Dunstan and Dymond, seemingly SO diametrically opposed t o my own, may possibly be due to one or more of the following circumstances :- (1.) To the presence of ether vapour instead of oxygen above the liquid.56 RICHARDSON: ACTION OF LIGHT ON PURE ETHER (3.) To the partial absor.ption by the glass of those rays which are (3.) To the presence of traces of reagents which decompose hydro- Taking these points into consideration, it is not, perhaps, remark- able that their results do not agree with those of other observers, and t,hey do riot appear t o be justified in concluding, as they do, that the experiments made by them " conclusively demonstrate that hydrogen peroxide cannot be formed from purified ether by exposing it to light, under ordinary atniospheric conditions in contact with air and water (ZOC.cit., p. 584)."" The experiivents described by me show, on the contrary, that by-drogen peroxide is formed in pure ether, even after treatment with potassium clichromate or hydriodic acid, when exposed to light,, provided- (1.) That the ether vapour in the bottle is replaced by moist air 01- (2.) That the bottles used are made of colourless glass. (3.) That the last traces of the reagents used in its purification are most influential in bringing about the change in the ether. gen peroxide. oxygen in the first instance. removed. Itz$wence of Temperature on the formation of Hydrogerz Peroxide in.Bther. The oxidation of ether at high temperatures has been investigated by Legler (Ber., 14, 602, 18, 3343; AnnaZen, 207, 381) and by Perkin (Trans., 1882, 41, 343), but it does n o t appear clear that hydrogen peroxide was amongst the products of decomposition ob- tained by these experimenters. It ww also observed by Dunstan aud Dgmond (Trans., 1890, 57, 585), that hydrogen peroxide was not formed when a mixture of ether vapour and oxygen was passed Over ~t~rongly heated pumice ; they, however, found that when cold water was in close proximity t o the heated vapours, the peroxide was formed in considerable quantities. Although I have been un- able to detect the prcsence of hydrogen peroxide in ether which has been kept in contact with moist oxygen in the dark, at ordinary tem- peratures, yet I have found that at compam.tively low temperatures * This, as Messrs. Dunstan and Dymoncl have since explained (Proc., 1890-91, p.147), applies to the conditions under which the first series of cxperinients was pel*- fdrmed, namely, diffused suiilight in London, and the electric arc-light. I n the second series (Trans., 1890, 988), with intense sunlight in a clear atmosphcre, hydrogen peroxide was formed in quantity sufficient to be detected by the chromic reaction. [EDITOR.]IN PRESENCE OF MOIST OXPIXEX. 57 this substance was formed. Ether and moist oxygen were heated together in the dark a t 60" for 40 hours; on testing the liquid, it was found that hydrogen peroxide had been formed t o a considerable extent.Again, when a similar mixture was heated in the dark for four days to a temperature ranging between 78" and 88", hydrogen peroxide was detected in the liquid ; in these experiments, the quantities of ether taken were such that it was not entirely converted into vapour. In a tliird experiment, the same quantity of ether as in the last case (contained in a sealed tube) was placed in a flask of 1000 C.C. capacity, which was filled with moist oxygen and sealed ; the tube was then broken, and the mixture of ether and oxygen exposed to a tempera- ture of 75-88'. Under these conditions, the whole of theliquid was converted into vapour ; after four days heating, the contents of the flask were tested for hydrogen peroxide, a.nd it was found that only an extremely minute trace of this substance was formed.The experiments so far described throw no light on the question whether the hydrogen peroxide formed in presence of ether is a direct product of oxidation of water present, or is due to the oxida- tion of the ether. As this point is of considerable interest, the following experiments seem to show that the formation of the per- oxide is due to the direct oxidation of the ether by light, as suggested by Berthelot, and that perfectly dry ether and oxygen give, after exposure, a compound which, on the addition of water, fornis hydro- gen peroxide. Et'her was dried by exposing i t to a large surface of metallic sodium contained in one limb of a bent sealed tube, and after 11 days contact with the metal, a portion of the liquid was distilled into the other limb, which had been previously drawn out. It was then sealed off, slid the distillate so obtained transferred to an outer tube, through which dry oxygen vas drawn for four days; i t was then sealed, and the inner tube broken. The niixture of ether and oxygen was tested after eight days exposure t o light, and gave the hydrogen peroxide reactions with potassium iodide and with titanic acid. In a second experiment, the mixture of dry ether and oxygen was exposed in the dark to a temperature of about 70" for four days ; in this as in the previous case, thc liquid was found t o contain hydrogen peroxide when tested with a solution of titanic acid. If sodium is capable of removing completely the last traces of moisture from ether, the formation of hydrogen peroxide in these experiments is not due to the direct oxidation of water, as 1 had at first supposed ; the results of other experiments, however, which are net yet completed, show that, under proper conditions, water itself is slowly oxidised under the influence of sunlight.38 BRAUSER : VOLLURIETRIC ESTIMATION OF TELLURIUM. Note.-In a subsequent paper, Dunstan and Dymond have published the results of further experiments on this subject (Trans., 1850, 57, SSS), in which they state that hgdrogen peroxide is formed by the action of sunlight on moist ether in presence of oxygen.

ISSN:0368-1645    

DOI:10.1039/CT8915900051

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

38 BRAUSER : VOLLURIETRIC ESTIMATION OF TELLURIUM. By BOHUSLAV BRAUNER, Ph.D., Piqofessor in the Bohemian University, late Berkeley Fellow of Owens College. IN my researches on tellurium (Trans., 1889, 382), 1 required a rapid and accurate process for its determination, but as all the known methods are gravimetrio, and weighed filters have to be used, the re- sults are not only liable to considerable errors, but also take R great deal of time and trouble. As no volumetric methods for the estimation of tellurium have been published hjt>herto, I have devised and worked out some of tliis clistract,er, a t first with a view to their technical application, but as the work progressed I studied the process, so as t o develop it into an accu- rate volumetric method, and I now beg to lay the results I ha\-e obtained before the Hociet,y.First i?fethocl. P?.inciZ~te.--olutions of telluriuin dioxide in hydrochloric acid are reduced by sbannous chloride, tellurium being precipitated, and stannic chloride formed. a. TeCI4 + 2SnC1, = Te + 2SnClI, 01- b. H2TeO3 + 2SnC1, $. 4HCl = To + 2SnC1, + 3H,O, or c. TeO, + 2SnC1, + 4HC1 = Te + 2SnC14 + 2H,O, The excess of reduced stannous chloride can then be determined by means of iodine solution rolumetrically : SnC1, + BHCl + I2 = SnC1, + 2HI. The method requires- a. A solution of stannous chloride, prepared by boiling about 80 granis of granulated tin with 200 C.C. of hydrochloric acid, until hydrogen is no longell evolved, pouring off, adding some 450 C.C. of hydrochloric acid, and diluting to one litre. The solution is preservedBRAUNER : VOLU,llETEIC ESTIXATION OF TELLURIUM. 59 in an atmosphere of carbon dioxide, and may be further diluted with water, according to the smaller or larger amount of tellurium which is to be determined. p.A solution of about 7 grams of iodine and 10 grams of potas- sium iodide in 1 litre of water. Detewninut.ion.-The bydrochloric solution of tellurium dioxide is brought into a measuring flask of 100 C.C. capacity, and the stannous solution added while the liquid is warmed. A t first a turbidity, con- sisting of finely divided telluriuni, is produced, but, as soon a s the stannous chloride is in excess, voluminous flocks of tellurium sepa- rate, and the liquid becomes perfectly limpid, especially after boiling. When the carcfuI addition of stannous chloride no longer produces a precipitate, freshly boiled water is added up t o the mark, the air in the neck of the vcsscl is displaced by carbon dioxide, by t,hrowing in some sodium hjdrogen carbonate, and the closed flask is cooled t o the 0rdinai.y temperature by immersing it in water.While this is taking place, the relation between the stannous chloride and t h e iodine solution is determined in the usual wag, using starch solution as indicator. When the flask containing the tellurium is cooled, it is iilled up to the mark, the whole mixed, and the excess of stannous chloride determined in a measured portion of the clear liquid by means of iodine solution. It is convenient to filter the liquid through a folded filter, or Fessenden’s modification of it (C‘henz.News, 60,102), in order to avoid the presence of finely divided tellurium, as this slowly decolorises iodine. The volume of iodine solution required for the whole It10 C.C. is calculated (neglecting tlie very small volume occupied by the telluriurn, as the balk of 1 gram of the latter is only 0.16 c.c.), and from this the amount of stannous chloride correspond- ing with it ; on subtracting this from the stannous chloride originally employed, the volume of stannous cb loride required for the pre- cipitation of tellurium is found. I n order to ascertain whether the reaction between stannous chlor- ide and a hydrochloric solution of tellurium dioxide* corresponds with the equations a, b, and c, given above, the following experiments were undertaken.The filtrates obtained after precipitation of the tellurium were tested for it, but none was found ; the precipitation under the given conditions ma^ therefore be regarded as complete. Starting w-ith the relations of the iodine solution to the stannous chloride solution, and to a solution of a known weight of arsenious acid, * Such a solution, as long as it is concentrated, contains yellow tcllnrium tetra- chloride, together with a hydrocliloric solution of tellurous acid, which is colour- less. The proportion of the latter increases on dilution, and at last the liquid becomes colourless.60 BRAUNER : VOLUMETRIC ESTIMATIOX OF TELLURTUM. the volumes of iodine and stannous chloride solutions, corresponding with a known weight of tellurium dioxide, were calculated, in accord- ance with the following proportion :-As,O, : 41 : ZSnCI, : TeOz.This supposes that the ratio of the quantity of iodine which is capable of converting 198 pts. of arsenious acid into arsenic acid is the same a s t,he ratio of a quantity of stannous chloride necessary for the reduc- tion of 159.6 grams of tellurium dioxide. Exp. 1.-A solution of sodium arsenite, containing 0.0495 gram As,O, (T&u mol.), and equivalent to 0,0399 gram TeO, (?Gm mol.), required 17-15 C.C. of iodine solution. 0.4803 gram of TeO, was dissolved in hydrochloric acid, and 55 C.C. stannous chloride solution added, 5 C.C. of which required 47.65 C.C. of iodine solution. 10 C.C. of the filtrate, the total of which was 100 c.c., required 31.65 C.C. iodine solution, and the total, therefore, 316.5 c.c., this being equivalent to 33.17 C.C.of the stannous solution, so that 55 - 33.17 = 21.83 C.C. stannous solution were used for the reduction of the tellnrium oxide, coresponding to 208.0 C.C. iodine solution. As 17.15 C.C. of the last correspond to 0.0495 gram AsZ03, and ought to correspond to 0.0399 gram TeO,, thc volume of stannous solution calculated for 0.4803 gmm ‘Ie02 beconies 21.66 c.c., and that of iodine solution, 206.5 C.C. This agrees as well with the 21.83 C.C. stannous solution, and 208.0 c.c. iodine solution actually employed, as could be expected, having regard to the different and indirectly coni- parable functions of the bodies entering into the reactions. The second mehhod of control was founded on the following more simple proportion :-TeO, : BSnCl, : 41.Exp. 2.-0-4499 gram dry iodine, resublimed in the presence of potassium iodide, was dissolved in potassium iodide solution, and it was found that 32.42 C.C. of the stavinons solution were required for its decolorisation, but 20 C.C. of the same stannous solution were found equivalent to 36.6 C.C. of thc empirical iodine solution, which there- fore contains 0.27754 gram iodine in 36.6, or 0.0075833 gram in 1 C.C. As 126.85 parts of iodine are equivalent to 39.9 pts. of tellurium dioxide, 1 C.C. of the iodine solution represents 0.0023353 gram TeO,. solution of 0.1765 gram TeO, in hydrochloric acid was boiled with 11 C.C. of stannous chloyide, and the excess of the laiter was deter- mined with iodine solution, of which 22.5 C.C.were required = 2.548 C.C. stannous chloride, as 1 C.C. stannous solution = 8.83 C.C. iodine solution, so that 11 - 2.548 = 8.452 C.C. stannous solution = 74.63 C.C. iodine solution were required for reduction. The weight of tellurium dioxide calculated froni these data is 74.63 x 0.0023853 = 0.1780 grani, instead of the 0.1765 gram taken. Exp. 3.-Another experiment of this kind yielded : Stannous solution = 11.0 C.C. ; retitration with iodine = 23.13 C.C. ; for reduction,QRAUNER : VOLUMETRIC ESTINATION OF TELLURIUM. 6 1 ---~-__I- C.C. 1 C.C. 5-63 19.37 17'20 g:ii 1 46.77' 6-32 10.68 stannous solution = 8.738 C.C. = 73.98 C.C. iodine solution = 0.1'7646 gram Te02, instead of the 0.1765 gram taken. Both these experimentas show that the reaction between slaiinous chloride and tellurium dioxide really corresponds with the equations a, b, and c.In actual practice the volumetric solutions were generally standard- ised by means of pure substances, the quantity of the latter being subsequently determined. I n accordance with this principle, the following experiments were made, the relation between the stannous. chloride and iodine solutions being as follows :- grains. 0.4322 0.3845 1.0436' 0'2348 Expts. 4- 7 . . )) s-10.. ,, 11-12.. ,, 13-14.. 1 C.C. SnC1, = 14.1 C.C. I = 0.02231 gram Te02. - 1 7 9 = 16.8 ,, = 0.03931 1 7 , = 8.83 ), = 0.02089 1 7 9 = 1.85 ,, = 0.00431 No. of Experi- ment. -- 4 5 6 7 8 9 10 11 12 13 14 -- ~- --- SnCl, added. ~- C.C. 25 21 55 17 5 14 6 back. -~ C.C. '19.5 54 -75 116 -04 s9 -1 8.5 163 *1 26 '0 22 * 5 23 -15 4 %5 7 -8.5 -- --- -- 0 -51 9-43 1 -55 2' 55 2 -62 2 -51 44 -24 4 -49 4 '57 4 *45 8 -45 8.38 20 -49 20 *76 --- TeOa f Olllld.-- grams . 0 '3839 1 '0492 0 -2383 - -- I 0 -1765 - 0 -1765 0 * 1797' 0.1'165 I 0.1750 Critical Remarks. It will be seen from tho above experiments that the results obtained by the stannous chloride method are sufficiently accurate for certain practical purposes. The following sources of error in this method must be noted, however. The stannous chloride solution is very easily oxidised by the action of the oxygen of the air, so that its strength continually diminishes, especially during the boiling, cooling, and subsequent filtration, as shown by the following experiment :- E X ~ . 15.--2 C.C. Snc1, solution, requiring originally 33.6 C.C.iodine solut,ion, was diluted with water, boiled, and after cooling filled UF to 100 C.C. Of this solution, 20 C.C. required 6.68 C.C. iodine solution;.62 BRAUNER : VOLTTM'ETRIC ESTINATION OF TELLURIUM. t,he whole 100 c.c., therefore, would require 33.4 C.C. iodine solution. After filtering, only 6-64 C.C. iodine were required for the $0 C.C. = 33.2 C.C. f o r the whole 100 c.c., so that the original strength, 2-60, becomes 1.99 in the first, and 1.98 in the second case. Owing to +his source of error, the stannous chloride in excess will be found somewhat smaller, and the amount of tellurium dioxide correspond- ingly larger than it should be. A comection corresponding to the blank experiment may he introduced into the quantitntive determina- tion, although, i f the method of cornparison (see Exps. 4-14) be employed, this would be necessary only when the volume of the stannous chloride used varies within wide limits.Other sources of error may also exist, although they cannot be ascei*tained with certainty. For instance, the tellurium probably carries down some tin with it as tellu~ide~ althongh this is doubtIess difficult to prove. It seems, however, from the results obtained, that this source of error, as also the effect of the varying amount of hydro- chloric acid present, does not affect the residt snriously. AppliciltioiL of the Method. To show the application of the method just described, the basic sulphate of tellurium was analysed. Exp. 16.-0.3198 gram of tellurium sulpliate was dissolved in hydrochloric acid and precipitated with stannous chloride solution, of which 15 C.C.was used. Excess determined with 32-75 C.C. iodine = 3-39 c.c, stannous solution, so that 11.61 C.C. stannous solution was used for reduction. As in Exp. 1, 0.4803 gram TeO, was indicated by 21.83 C.C. of the same stannous solution, the 11 61 C.C. = 0.25544 gram TeOz. This gives for 100 parts of the salt- Calcirlated for TeoO,,S03. Found. TeOa .. .. .... 79.95 m-sa Second Method. Kessler (Pogg., 95,204 ; 118, 11 7) has shown that, on the addition D f chromic acid t o hydrochloric solutions of arsenious o r antimonious oxides, these are converted into arsenic and antimonic acids. A similar reaction might be expected to take place with a soIution of tellurium dioxide, and it was supposed that the rextion would be tlie following :- d.3HZTeO3 + K2Cr207 + 8HC1 = 3H,TeOl + SKC1 + Cr2CI, + 4H,O, orBRAUNER : TTOLUMETRIC ESTIMATIOX O F TELLURIUM. 63 e. 3TeO2 $. K2Cr207 + 8HC1 = 3Te0, + 2KC1 + Cr,C1, + f. 3Te02 + K2Cr207 + 4H2SO4 = 3Te0, + K,SO, + Cr,(SO,), To a hydrochloric solution of tellurium dioxide, after dilution with water, potassium dichromate solution W R S added in excess, and after some time the excess of dichromate was dctermined by means of a solution of ammonium ferrous sulpliate, which was added until a drop of the solution brought into a fresh dilute sohxtion of potassium ferricyanide gave a dist>inct blue coloration. The relation between the dichromate and the ferrous solution was determined in the same manner .A series of experiments was first made, in order to see whether the reaction between tellurous and chrclmic solutions corresponded with the above equations d, e, andf. 2.5 grams of potassium dichromate was dissolved in 1 litre of water, and 10 C.C. of this solution were found to oxidise 2.83 C.C. of the ferrous solution. Exp. 17.-0.048 gram arsenious acid was dissolved in sodium carbonate, and the solution then acidified with hydrochloric acid. The solution was found t o require for oxidation 18.63 C.C. K2Cr207 solution, which corresponds with 0.07738 gmrn Te02, f o r 198 parts of As203 (1 mol.) are oxidised by the same quantity of dichromate as 319.2 parts of TeO, (2 mols.). The 0.0'737 gram of TeO, used for the experiments bt?low ought to require 17.3 C.C.of K,Cr,07 solution. Exp. 18.-0*1064 gram pure iron was dissolved in dilute sulph- uric acid, and 35-95 C.C. of the chromic solution was used for its oxidation. According t o the equation 4H,O, 01' also + 4H,O. 6FeS04 + K,Cr,07 + 7H2SO* = 3Pe2(S04), + K,SO, + Cr~(SO~), + 7HzO, 336 parts F e (6 atoms) and 478.8 parts TeO, (3 rnols.) require one and the same quantity of dichroniate for oxidation, so that 1 C.C. of t h e above chromic solution indicates 0.004218 gram TeO,, and 0.0737 gram Te02 should require 17.5 C.C. dichromate solution. The styength of the dichromate solution may also be calculated from the quantity of dichromate contrained iii it. As 295.36 parts KzC1-207 (1 rnol.) oxidise 478.8 parts TeO, (3 rnols.), 1 litre cf the solution, contsining 2.5 gram K2Cr207, oxidises 4.1493 grams TeO,, so that 0.0737 gram TeO, requires 17.8 C.C.The following first series of approximate results was obtained :-64 BRAUNER : VOLUMETRIC ESTIMATION OF TELLURIUM. X2Cr,0, added. --- C.C. 18 30 20 25 30 30 30 No. ?f experi- ment. -- 19 20 21 22 23 24 25 26 C.C. 1-3 2.4 1-8 0'1 2 -4 1 -9 1 -9 FeSO, = X2Cr,07. L----d back. ----- C.C. - 2 . 3 -4 -5 - 3 - 3 -@ .2 -4.0 -3'4 -3 *4 HC1 Jwe- sent;. C.C. 20 - - 10 20 10 10 I - B2O pre- sent. C.C. 100 10 10 100 100 100 200 200 - K2Cr20r added. -- C.C. 35 35 36 40 -5 40 40 20 20 E2Cr,0j for oxidation. E€,SO,1/1 present. --- C.C. - 10 10 10 - - - 1 -- C.C. 4 -6 4 -4 4.7 5 *9 5 -7 5.7 1 *o 0 - 7 C . C . -16.3 -15.5 - 16 -4 - 20 *7 - 20 -0 - 20 '0 - 2.8 - 2 - 5 C.C. 19 *7 19 -5 19 -6 19 *8 20 '0 20 -0 17 -2 17 -5 The duration of interaction between the chromic and tellnrous solutions was one hour in Experiments 18, 19, 20 ; 16 hours in 21, 22, 23 ; tlwo minutes in 24 ; and five minutes in 25.Another solution containing 0.1096 gram TeOz would require, when calculated from the quantity of dichromate dissolved, 26.4 C.C. of dichromate solution. No. of experi- ment. K2Cr2oj. for oxida- tion, -- C . C . 15 -7 26 -5 16 -7 243 '8 25 -6 26 *6 26 -6 HZO present . HC1 present. -- C.C. - 10 10 10 10 10 10 C.C. 100 100 100 100 100 100 1.00 27 28 29 30 31 32 33 Duration of experiments :--Experiment 27, 2 min. ; 28, 1.5 min. ; A solution of 0-0828 gram TeO,, requiring 20.0 C.C. K2Cr207, was 29, 2 min. ; 30, 10 rnin. ; 31, 15 min, ; 3.2 and 33, 24 hours.used in the following experiments :- No. of experi- ment. K2Cr,07 for oxlda- tion. FeSO, = K,Cr,Oj. L-_,---J back. C.C. C.C. 5 -6 -. 10 -0 5 -6 - 10 -0 5.8 - 10 ' 2 5 . 6 - 10 -0 5.7 -10.1 5 -6 - 10 9 HQO present. HC1 present. K,Cr,O j added. C.C. 3 10 3 10 20 30 C.C. 30 30 30 30 30 30 -2 C . C . 20 -0 20 -0 19 -8 20 *o 20 -1 20 *2 C . C . 100 100 100 100 100 100 34 35 36 37 38 39BRAUNER : VOLUXETRIC ESTIRIATIOX OF TELLURIUM. 6 5 Duration of experiments :-Experiments 34 and 35, 24 hours ; 36, 37, 38, and 39, 10-15 minutes. From these experiments, the first series of which is only approxi- mately accurate, it will be seen that the oxidation of tellurous acid is the more complete, the longer the action of the dichromate, the largor the volume of the dichromate solution added, and the larger the quantity of hydrochloric acid present.In sulphuric acid solution, the reaction corresponds with the equation 6 , but requires more time than in hydrochloric solution. The last series of experiments was made with a standard solution of pure potassium dichromate. The purest commercial salt was purified by fractional solution in and disturbed crystallisation frcjm water, the middle portions only being used. 2.5936 gram (-& mol. weight) was dissolved in water and diluted to 1 litre, 1 C.C. of tl:e solution indicating 0.004788 gram TeO, (i$v mol. weight). 3.1880 grams TeOa was dissolved in 50 e.c. of hydrochloric acid and diluted to 100 c.c., so that 5 C.C. of the solution taken for each experiment contained 0.1594 gram TeO,.In each experiment, 20 C.C. concentrated hydrochloric acid was added, and water to make u p the total volume to 100 C.C. The volume of the dichromate solution was nearly equal in all the experiments, so that the whole series of experiments was carried on under precisely similar conditions, except that the duratEioll of the action was varied, as seen from the last column. The volunie of dichrornabe solution necessary for the complete oxidation of ci-1594 gram TeO, is = 33.5 C.C. No. of experi- ment. -- 40 41 42 43 44 45 46 47 48 49 50 51 52 g2cr207 added. -- C.C. 43 -4 40 -0 40.4 40 -4 40 -0 40.0 40 .o 41.0 40 -5 41 '0 40.5 40 '0 40 .O FeSO, = K,Cr207. L--,.--J back. -- C.C. 13 .9 10 -7 6 . 1 4.9 4 5 4.4 4.3 8.9 4 .4 4.7 4 *2 4 -0 3 - 8 -- C.C. - 23 *1 -17 ' 8 -10 *4 - 8 -2 - 7 .5 - 7 -3 - 7 - 2 - 8 -2 - 7 -3 - 7 '7 - 7 - 1 - 6 . 6 - 6 . 3 K2Cr207 for oxidation. -- C.C. 20 '3 22 *2 30 '0 31 -8 32 *5 32 *7 32 '8 32 ' 8 33 ,2 33.3 33 '4 33 *4 33 *7 Time. 11. 111. CI 1 0 2 0 7 0 10 0 17 0 30 1 0 1 15 3 53 5 40 18 0 18 0 25 C On graphically representing the data obtained in this series by eurve, the volumes of dichromate solution standing as ordinates a i d 7OL. LIX. F66 BRAUNER : VOLUNETRIC ESTIhldTION OF ThLLURIUM. the time of interaction 8s abscissz, a very regular hyperbola, running through the points, is obtaiiied, as seen from the Plate. Cq-itical Remarks. The hyperbola, on reaching the point y = 33.3, does not take a diyection parallel to the axis z, but rises slowly further on, but as after one hour's action almost all the tellurous acid is converted into teIluric acid, a secondary retiction may be assnmed to take place.The experiments were made a t a summer temperature of 25-30", mid a feeble, peculiar odom, like that of chlorine or ozone, was observed after some time, which must be due to the action of the mixture of chromic and telluric acids on the hydrochloric acid, ams chromic acid alone in the presence of hydrochloric acid is found to require the same amount of ferrous solution for titration after 24 hours as immediately after mixing. The mixture of chromic and telluric acids, therefore, will require less ferrous solution, and the quantity of chromic solution required for oxidation will be fouiid somewhat larger. The secondary reaction may take place in the following two phases :- g.H,TeO, + 2HCI = H,TeO, + GI, + H,O, and h, 3H,TeO, + K2Cr207 + 8HC1 = 3H,Te04 + 2KLc1 + Cr,CI, + 4H,O. The observed rise of the nyperbola may be dne t o this reaction. Another source of error is due to the fact that the blue coloration with potassium fcrricyanide, which is produced when all the chromic acid has been destroyed by the ferrous sulphate solution, appeam distinctly only when 100 C.C. ol the solution contains an excess of 0*4-0.5 C.C. ferrous solution. On applying this correction t o the process of determining the relation between the ferrous and chroilzic solutions, as well as to the final titration of the tellurous solution, the result is very considerably influenced. Uncorrected:-90 C.C. K,Cr,07 = 12.07 C.C. FeS04, and 41 C.C. K,Cr,O, - (4.65 C.C. FeSOa = 7.7 C.C. K,Cr,O,) = 33.29 C.C. K2Cr,07. Corrected:-20 c c. K,Cr,07 = 11-62 C.C. B'eSOo, and 41 C.C. K,Cr207 - (4.20 C.C. FeSOb = 7-23 C.C. K,Cr,O,) = 33 77c.c. K,Cr,O,. The correction which must be applied to the volume of chromic solution used for oxidation is +0.5, abd we see that according to this the theoretical quantity of 33.3 c.c: K,Cr207 is required after an interaction of one hour. Rut i t is uncertain whether one and the same correction can be applied both in standardising and in making the final experiment. A s the reaction between tellurium dioxide and chromic acid inE BRAUNERCOHEN ON DTBENZANILIDE. 67 hydrochloric acid solution requires at least one hoixr for completion, i t is perhaps rather of theoretical interest than useful as a practical uolu me tr ic method. Further volumetric methods for the determiiiation of tellurium will be described in a future paper.

ISSN:0368-1645    

DOI:10.1039/CT8915900058

出版商:RSC    

年代:1891

数据来源: RSC

摘要:

COHEN ON DTBENZANILIDE. 67 V I I L - N o t e om Dibenxnnilide. By J. €5. COHEB, Ph.D., Owens College, nilanchester. THE researches of Paal and Otten (Ber., 23, 2587), and of Pictet (Ber., 23, 3011), which have recently appeared, induce me to publish the following observations, which 1 made some time ago. I n the latter portion, I was greatly assisted by Mr. F. Brownsword, B.Sc., a former stxdent in this laboratory. When a mixture of phenjlthiocarhimido with benzaldehyde is heated for some houys at 190", sulphuretted hydrogen is evolved, and several products are formed. These coiisist mainly of benzanilide and benzaldehyde-aniline, and form a semi-solid mass from which the benzanilide may be isolated by filtration. The latter was recrystal- lised from alcohol and melted at 161-162".When heated in a sealed tube with concentrated hydrochloric acid, it splits up into aniline and benzoic acid. The following result was obtained on analysis :- 0.1995 gram gave 12.4 C.C. of N at 16.5" and 761.2 mm. Pound. Calculated. N.. .... .. 7.36 7-10 The reaction is a, complex one, and was not studied further. A similar reaction described by Losanitsch (Bey., 6, 17C;), and repeated by Higgin (Trans., 1882, 132), consists in heating phenylthiocarbimide with benzoic acid at 220". A solid product melting at 160" is thus formed, which is stated t o be dibenzunilide; but in neither paper is any analysis given. The similarity of the two reactions, and the alleged difference in the product obtained, induced me to repeat Losanitsch's experiment. The product, of the reaction is a solid, crystalline mass, which, wheu recrystallised f r o m alcohol, melted at 161-162".The following result was obtained on analysis :- 0.2150 gram gave 13.4 C.C. of N at 13.4" a d 7'75.5 mm.68 COHEK ON DTBENZXNILIDE. Calculated for Calculated f o r Foiind. benzanilide. dibenzanilide. N.. ...... 7.60 per cent. 7-10 4.63 The compound is obviousiy beuzanilide. 'In t h i s as in all siibsequent amalgses, the nitrogen nlnne has heen determined, aifi this suffices to establish the identity of the compound with benzanilide or dibeiizanilide. To confirm the above resnlt, and t o compare the product with dibenzanilide, I attempted to prepare the latter by the method of Gerhardt and Chiozxa (Ann. Chim. P72?ys. [3], 46, 129) by heatinq a mixture of benzanilide and benzoyl chloride in niolecular propor- tion a t 160-180".In doing so, I followed in detail the method of Oerhnrdt and Chiozzn : but was entirely unsuccessful in obtaining dibeuznnilide." The substance was purified by the method given in their paper, namely, by digesting with soqium carbonate solution, washing w i t h water, and recrystallising the product from alcohol. Prepared in this was, the cornpound obtained is a white, granular mass consisting of acrgregates of microscopic crystals, differing entirely in appewance from the glistening plates of benzanilide. The substance, which was evidently impure after two recrgstallisations, melted a t 158", and gave the following results on analysis :- 1. 0.2020 gram gave 13.1 C.C. of N at 24" and '759.9 mm.2. 0.2168 ,, ,? 14.2 ,, ,, 15.5 ,, 747.8 ,, Nitrogen found. 1 ............ 7.54 per cent. 2 ............ 7-64 ,, The above process was then repeated under a variety of different coiidit,ions. The mixtme of benzanilide and benzoyl chloride was heated a t 200", 220°, and 230" f o r different periods from 3 to 12 hours, and also in sealed tubes a t 180". In the latter case, it may be mentioned that no excess of pressure was observed on opeiiing the tubes. This would prove that 110 great * The authors state that gaseous hydrogen chloride is evolred during the re- action, but this is not the case. The evolution of hydrogen chloride is not more apparent than when benzoyl chloride alone is hmtcd a t the same temperalure in an open vessel, as I observed by placing benzoyl chloride in a flask in the same bath with the mixture.There was no marked evolution of gas in either case. Gerhardt and Chiozza obtained, as a result of one analysis, 5 per cent,. of nitrogen in place of 4.6 per cent. The percentage, which I recalculated from their figureq, should be 5-22 per cent. This is undoubtedly due to the fact that the benzanilide, which remains unaltered in the process, contains benzoic acid, from which it, is ex- ceedingly dificrilt to free it. The low melting point (137') may also be accounted for in this way.COHEN ON DIRENZANIL'TDE. 69 evolution of p s had occurred during the heating. I n the many an;llyses made of both the impure and purified product, in not one instance did the percentage of nitrogen fa11 below 7 per cent.The following are some of the results of the analyses of the pro- ducts obtained at 180". 1. 0.2170 gram gave 13.4 C.C. of N a l 36" and 750 mm. 2. 0.2068 ,, ,, 12.65 ,, ), 12.9" ,, 739.85 mm. 3. 0.2160 ,, ,, 13.4 ,, ,, 13.5" ,, 750.9 ,, Per cent. of N found 1. After heating in a sealed tube for 4 hours at 180" and Melting point 2. After heating at 180" for 4- -5 hours and crystallising 3. Aft,er heatiyg at 180" for 4-5 hours and crystallising crystallising the product three times. 158 " .......................................... 7-19 o n c e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.13 t h e e times.. .................................. 7.34 The following experiment was then carried out :-45 gi'ams of pure benzanilide melting at 160-160*5" were heRted at 180" with 34 grams of benzoyl chloride for five hours, and the liquid product poured whilst hot into a large volume of cold water.To prevent possible decomposition of dibenzanilide, t,he product was digest ed with sodiiim carbonate solution in the cold, by adding, successively, small quantities of a solution of sodium carbonate until an alkaline reaction remained perma'nent. It was then filtered, dried, and weighed. 43 grams were obtained. The substance was then sub- mitted to a process of recrystallisation from alcohol, and the melting point of each product determined as follows :- F i ~ s t CrystaZZ1:sation.-Granular mass, m. p. 1.55", also a minute quantity of needle-shaped crystais melting at 156". Second 01.1Jsttallisation.-~hite grains, m.p. 157-158". A few needle-shaped crystals again formed and were carefully separated. Tltese melted at 157". Third CrystaZliPation.-Appearance similar to the previous product, m. p. 157-158". Fourth CrystaZZisatio7z.-Appearance unchanged, m. p. 1.57-159'. No needles. Fifth Cry.FtalZ~.scction.-The crystals were more distinctly tabular., and had the characteristic glistening appearance of benzsnilide, m. p. 157-159'. By evaporating tbe mother liquors from the separate crystallisa- tions, more granular crystals mixed with a brown resinous matter No needles were present.70 COHEP; ON DIBENZANILIDE. separated, and from the last mother liquor, a small amount of benzoic acid was obtained. The presence of benzoic acid is not easy to explain.The amount of brown, resinous matter increases with the temperature at which the reaction is carried out. I n an experiment made at 230", the product was very impure from this cause, and after five crystallisations from alcohol, only melted slowly at 140-151". Under these conditions, the percentage of nitrogen in the compound was always above tlhe calculated amount. The quantity of the needle-shaped crystals was too small to allow me to do more than make a determination of the melting point. I attempted to obtain more of them by evaporating the mother liquors and dropping some of the needles into the solution t o bring about crystallisation. On the assumption that benzanilide might be dimorphous, I also added a crystal or two to a saturated solution of pure benzanilide.I n both cases I was unsuccessful in obtaining the needles. The literature of the subject would be incomplete without reference to the work of Steiner on tribenzhydroxylamine (AnnaZen, 178, 235). The author states that by heating a-tribenzhydroxylamine in a closed tube, dibenzanilide is formed and carbon dioxide evolved. The evidence for this is based on the decomposition of about 1 gram of substance, which gave a volume of gas roughly corresponding to the amount required by the decomposition of the substance in the manner indicated. He admits that the product does not resemble dibenz- anilide, that it does not smell of phenyl cyanate; but possesses a strong odour of bitter almonds, and is to a great, extent soluble in cold ether. The residue insoluble in ether, after cry stallisation, formed small needles with the melting point 161".Steiner, finding that the melting point did not agree with that of Gerhardt and Chiozza's compound, repeated their experiment of heating together benzoyl chloride and benzanilide. The product, after recrystallisation, had the required melting point of 161". The analysis gave 5.38 per cent. of nitrogen in place of 4.63 per cent. Like G-erhardt and Chiozza, Steiner probably obtained benzanilide containing benzoic acid." The author concludes by stating that the products of decomposition of a-tribenzhpdroxylamine " are not wholly, apparently not even to any extent,, dibenzanilide and carbon dioxide." We map then conclude that, up to the present, dibenzanilide has This compound may therefore be dibenzanilide.* This experiment was again repeated in 1882 by Higgin (Trans., 1882, 132), at :I, temperature of 230'. The author obtained needles melting at 13G0, but as he only determined the percentage of carbon in the compound, viz., 79-60 (benzanilide has 79-18 and dibenzanilide 79.73 per cent.), no satisfact,ory conclusions can be drawn.‘iz EASTERFIELD : PHEXYLBROJXACETIC ACID. not been prepared, at any rate not in the pure state. The synthesis of this compound I desire to reserve for future study. Paal and Otten, as well as Pictet, point out in the papers referred, t o a t the beginning of this note, that by the action of bcnzoyl chloride on acetanilide, benzanilide and acetyl chloride are formed in theoretical quantities, and, from this and nther experiments, state that, in this reaction, the acid chloride of higher molecular weight replaces that of lower molecular weight in combination with tho amine. I had occasion incidentally to try and replace the amido-hydrogen atom in benzanilide by acetyl, and attempted this by heating benzanilide with acetic anhydride and a small quantity of fused sodium acetate. The benzanilide was converted into acetanilide which melted a t 112’. It appears, therefore, that under these con- ditions the action is reversed. I intend to t r y this reaction with the ot.her homologues of benzanilide. This is an additional confirmation of the fact that the replacement of the second amido-hydrogen atom by an acid radical in aniline is not readily accomplished by the ordinary methods.

ISSN:0368-1645    

DOI:10.1039/CT8915900067

出版商:RSC    

年代:1891

数据来源: RSC

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EASTERFIELD : PHEXYLBROJXACETIC ACID. IX.-Pl~enylbromacetic Acid, an appayent Exception to the Le Bel- Van’t I€(# Hypothesis. By T. H. EASTERFIELD. VAN’T HOFF, in his “Dix Annhes dens 1’Histoire d’une Thkorie,” after referring to the reservations which accompanied the introduction of his fundamental idea, expresses his views in the following sentence (‘i Dix Annkes,” p. 49) :-‘‘ Or depuis lors la dkcouverte de l’act.ivit6 chee l’iodure de l’alcool amyl secondaire CHI*CH3mC3H7, par M. le Bel, a prouvk que mhme la ditI6rence entre l’hydroghe et un atome haloghe suffit A la production du pouvoir rotatoire ; depuis lors il parait que toute restriction a perdu sa raison d’ktre.” Up to the present time, however, this amyl iodide of le Be1 appears to stand alone as the only active compound in which we have reason to bclieve that a halogen is united to the asymmetrical carbon.It therefore seemed desirable that similarly constituted haloid deriva,. tives should be prepared and studied. Accordingly, at the Yuggestion of Professor Emil E’ischer, I have attempted to prepare other active substances of the type alluded to, and although the results obtained so far are only of a negative character, they may perhaps possess sufficient interest to excuse their presentation before the Society.76 EASTERPIELD : PHENTLBROJIACETIC ACID. Active mcndelic acid was chosen as the parent substance ; it was prepared from amygdalin according to the directions given by Lewkowitsch (Bey., 16, 1565) ; 1 gram of the acid was sealed up in ;I tube with 10 to 15 times its weight of fuming bpdrobromic acitl saturated a t 0".The mandelic acid rapidly dissolved, yielding a 'clear solution. The tube was now placed in a water-bath a t 50' and maintained a t that temperature for two hours ; a t the end of that tlime *the rniandelic acid had becouie transfoi*med into phenylbromacetic; acid, C,H,-CHBr.COOH, most of which had separated as a light brown oil ; this solidified on cooling, and after recrystallisation from boiling light petroleum showed a melting point of 7E?-80°. Tho alcoholic solution of the brominnted acid was absolutely inactive ; the melting point of the acid corrcsporids with that of the infictive brominated acid prepared from inactive mandelic acid by the same process. On gently warming the acid with dilute soda soluti(8n, acidifying, and extracting with ether, it yielded inactive mandelic acid melting a t 118".&ni1ai*ly, plienj-lchloracetic acid, prepared by the action of hydro. chloric acid on active mandelic acid, was found t o be inactive and to correspond in melting point and general character with the inactive synthetical acid. With fuming hydrochloric acid, however, a tempera- ture of 95--100" was necessary in order to start the reaction. It was not found possible to prepare an active chlorinated acid by the action of phosphorus pentachloride on an ethereal solution of actire mnridelic acid. Fuming hydriodic acid appears to have no action c n niaiidelic acid a t low temperatures ; at the temperature of the laboratory in sunimw, reduction took place gradually, no iodcr-acid being formed.The resoliltion of the halogenated acids by means of the alkaloid salts was also attempted but without success; the chlorinated and brominated acids are slowly decomposed even by cold water, and the alkaloids a t once remove the halogen atom. The difficulty of finding a suitable solvent prevents these substances being submitted t o the action of organised ferments. These remarks apply equally to bromosuccinic acid, with which some experiments were tried. Kekul6 (Awnalen, 130, 21) has prepared! bromosuccinic acid by the long-continued actiou of hydrobrornic acid on active malic acid a t 100". Here again the brominated acid -as inactive, and yielded inactive rrialic acid on treatment with moist silver oxide. Kekule remarks that it would have been oiily reasonable to expect an active brominated derivative to have been formed under these circum- stances, and surely the same remark holds good in the case of the reautiou between hydrobromic and active mandelic acids a t so low a temperature aa 50".In the case of malic acid, it may indeed beACTION OF HEAT ON NITROSTL CHLORIDE. 73 supposed t h a t malelic acid has been first formed, that this has been converted into fumaric acid, and has then taken up the elements of hydrobromic acid to form the inactive bromosuccinic acid ; such an assumption is impossible in the case of mnndelic acid. It would be indeed rash to generalise from the few facts before us, but the possibility certainly seems t o suggest itself that such strongly negative radicles as chlorine and bromine cannot be introduced by subst,itution into an asymmetrical active group without destroying the activity of the molecule. This might he due either to the fact that there is something in the nature of these atoms themselves which prevents activity in their compounds, or what is perhaps more likely, because the introduction of so chemically potent an atom produces such a disturbing effect on the whole molecule that a general re-arrangement of its atoms becomes necessary ; in other words, that intramolecular change takes place. The above investigation was carried out in the laboratory of the University of Wurzburg. I take this opportunit'y of expressing my deep indebtedness to Professor Fischer for the characteristic kindness which I have received at his hands.

ISSN:0368-1645    

DOI:10.1039/CT8915900071

出版商:RSC    

年代:1891

数据来源: RSC

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ACTION OF HEAT ON NITROSTL CHLORIDE. 73 X-Action of Heat on ATitrosyl Chloride. By J. J. SUDBOROUGH, B..Sc. (Lond.), A.I.C. (Associate of the Mason College), and J. H. MILLAR. IT is well known that nitric peroxide, Nz04, begins t o dissocide at temperatures just above the boiling point of the liquid. When the gas is heated, dissociation into nitrogen dioxide is far advanced, according to Playfair and Wanklyn at a temperature of 97*5", and is complete, according to Deville and Troost, a t 140" (Compt. rend., 64, 237). Richardson has studied the action of heat upon this compound n t higher temperatures, and has found that a t 620" nitrogen dioxide is cornpletely dissociated into nitric oxide and oxygen (Trans., 1887, 51, 397). We determined to examine the action of heat i n like manner upon nitrosyl chloride, the only known oxychloride of nitrogen, as i t seemed probable that it would dissociate into nitric oxide and chlorine more readily than nitrogon dioxide splits into Eitric oxide and oxygen.TOL. LIX. a7.3- SUDBOROUQH: ACTION OF HEAT To elucidate this point, we undertook several series of experinien ts, of which +his paper contains a brief account. Prepnration .f Nitrosy1 Chloride. As a means of preparing the chloride, we invai-iably iised nitroayl sulphate (chamber crystals) and sodium chloride. The sulphate we obtained by passing the red gas evolved from copper and nitric acid or white arsenic and nitric acid into sulphuric acid. The red fnmes were first passed through a Liebig conderiser with a Woulff's bottle attached, so as to condense any nitric acid which might pass over, and all traces of moisture were removed by interposing a calcium chloride tube.The purified gas was then passed into the sulphuric acid, That these precautions were necessary was proved by t,he fact that our first sdphate--prepared by merely paseing the nitrous fumes into sulphuric acid without previous drying-contained a small amount of nitric acid, and the chloride prepared from it always contained traces of nitrogen peroxide and hydrochloric acid, the former of which was readily detected by its absorption spectrum. When the nitrous fumes had been passed into the sulphuric acid for some eight or nine hours, small crystals of nitrosyl sulphate appeared ; the reaction was then stopped, as the sulphate in a semi- liquid form was much more convenient.The sodium chloride used was merely common salt thoroughly dried. The two salts were mixed together in a Wurtz's flask, and the nitrosyl chloride, which was evolved on gently warming, was passed through a calcium chloride tube. That the gas thus evolved was practically pure nitrosyl chloride, was proved by estimating t,he amount of chlorine in a given weight of the gas. Vapour Density at Ordinary Te?npemtu?.es. The vapour density of nitrosyl chloride at ordinary temperatures had been previously determined by Tilden (Joum. Chem. SOC., 1874, 27, 632). From his results, i t was clearly established that the mole- cule of the gas at ordinary temperatures is represented by tlie formula NOCl, and iiot by any multiple of this.Density found. 33.25 Calculated for NOCl. 32-67 Our investigations consisted of determinations of the vapour density at temperatures ranging from 15" t o 985". Where possible, the uensity was obtained by weighing the gas, and checked by esti-ON NITROSYL CHLORIDE. 75 mating the chlorine; but, in some cases, we had to rely mereIy on the amount of chlorine found in order to calculate the density. In order t o fill the bulbs with the gas, we used one of the two following methods : - (1.) Condensing the gas by placing the bulb in a freezing mixture, till several cubic centimetres of the liquid were formed, and then allowing it to boil off (b. p. -8O). In this case, we found it very requisite t o have the bulb perfectly dry, and to have the outlet tube as far removed from the freezing mixture as possible, as the moisture which condensed around the cold tube readily decomposed the chloride as it passed into t'he air, and the nitrous and hydrochloric mids thus formed would readily find their way back into the bulb. (2.) By passing the gas through a bulb open at both ends t'ill all the air was expelled.We usually let the gas pass through for from 30 to 45 minutes. ,Sulphuric Acid Bath. Our first set of experiments was made at temperatures between 15" and 165". The method used was that of condensing the gas in the tube. The kind of tube we found most convenient, both for fittirig in the bath and also for obtaining the liquid free from moisture, is that represented in the figure. The bulb had two openings, bhe larger one, which was wide enough .to allow an ordinary piece of glass tubing to pass down, was ground, and had a glass stopper to fit, whilst the smalier one consisted of a long narrow capillary.The gas was passed in through the wide 6 276 SUDBOROUGH : ACTION O F HEAT neck by means of a piece of glass tubing which reached t o the bottom of the bulb. When a quantity of liquid was condensed, the neck was stoppered, and a cap placed over the end of the capillary. The bulb was cleaned, and the cap removed. It was then put icto the sulphnric acid bath, which was large enough to cover the bulb up to the stopper. The temperature was slowly raised, and the bath kept at the required temperature for 10 minutes. The cap was then replaced, the bulb removed, cleaned, and inverted in distilled water ; the cap was removed, and the water allowed to enter.The solution thus obtained was mixed with excess of ammonia, and evaporated on the water-bath to dryness in order t o get rid of all nitrite; the residue was then dissolved, and the solution titrated with decinormal solution of silver nitrate. From the amount of chlorine found, the vapour density was readily determined. Three cloterminations made in this way at 15' gave a mean yesult of 32.5. Experiments conducted in the same way at 65", 115", and 165' gave results which showed that no dissociation had taken place. In all cases, the density came out above 32. The density according to theory is 32.67. Bath of Methyl Xnlicylate Vapour. We next proceeded to heat the gas in a bath of methyl salicylate vapour, the temperature of which was 222".In this set of experi- ments, the gas was allowed to pass through the bulb for about 45 minutes. The bulbs used were merely large boiling tubes of about 150 cubic centimetres capacity drawn out at both ends into fine long capillaries. When the gas had passed through for the allotted time, one end was sealed off; the bulb was then lowered into the bath, and the open end allowed to project through the cork; this open end was fitted with a smaller bulb containing nitrosyl chloride, in order to prevent diffusion during the experinien tr. The salicylate was then boiled, and after the bulb had been in the vapour for about 10 minutes, the open end was sealed off. The bulb was then removed, allowed t o cool, and weighed; and from this weight the density was calculated. The end of the capillary tuba was afterwards broken off under water, the chloride dissolved, and the chlorine estimated as before; this served as a check on the density determined by weighing.Three experiments were conducted at this temperature ; the resulting density was 32.3, hhus indicating that no dissociation had taken place. Bath of Sulphur Vapour. Our next experiments were conducted in a bath of sulphur vapour. The vessel in which the sulphur was boiled was not of very largeON NITROSYL CHLORIDE. i 7 dimensions, and consequently the vapour became superheated. It was, therefore, necessary to determine the temperature by means of an air thermometer. This was readily d-one by taking a dry bulb of approximately the same size as the one used for the nitrosyl chloride, and fusing off when it had been in the vapour f o r 10 minutes.When cool, it was opened under water, and the volume of residual air determined ; from this and the total capacity of the bulb the tempe- rature was easily calculated. Three temperatures determined in one day only varied by 7" ; the numbers found were 690*6", 692.3", and 697.6". Four determinations of the density were conducted in the sulphur vapour. I n the first two, we liquefied the gas in the bulb, and allowed all excess to boil away after the neck had been drawn out into a long capillary. At first, we experienced great difficulty in keeping the bulbs free from moisture whilst the gas was passing in ; we eventually got over this difficulty by fixing a long T-tube on t o the neck of the bulb, and leading the gas through a capillary which passed down the T-tube, and reached to the bottom of the bulb, where it was condensed.I n the last two experiments conducted at this temperature, we merely passed the gas through the bulbs for about 30 minutes. The four results agreed fairly well, ranging from 32.3 to 33.1, and thus they indicate that no dissociation had taken place. Ah-bat h. We next made two determinations of the density in an air-bath, which was heated by means of four large Buzlsen burners. The temperature was determined both before and after each experi- ment by means of air thermometers. The bulbs were filled with the chloride by passing the gas through, and the two following results were obtained : - Temperature...... 796" V. d. . . . . 31-36 Temperature.. .... 816" V. d. ..... 91.00 These numbers indicate a percentage decomposition of about 13. Combustion Furnace. Our last experiments were conducted in a combustion furnace. We first used a method similar to that adopted by V. Meyer and Ziiblin in their investigations on chlorine, oxygen, &c., at high temperatures (Berichte, 12, 1430). The tube used was an ordinary piece of combustion tubing, the same length as the furnace ; t o one end was fixed a tap, whilst the other was drawn 08 into a capillary.78 SUDBOROUGH : ACTION OF HEAT A determiuation of the temperature was made both before and after each experiment. The tube was first dried by aspirating dry air though it4 for half an hour whilst tho tube was red hot.The tap was then turned off and the tube allowed to remain at the temperature of the furnace f o r 10 minutes ; the residual air was then measured by driving i t into a Schiff’s nitrometer, filled with strong caustic potash solution. A stream of carbon dioxide, dried by passing through two sulphuric acid tubes, was nsed for driving the air over. The carbon dioxide, in its turn, was displaced by the nitrosyl chloride, which was allowed to pass through the tube for about half an hour. A flask was attached to the capillaryat the end of the tube in order t o prevent diffusion. That a certain amount of dissociation did take place was proved by the fact tthat the gas which passed out of the flask turned red on meeting the air, thus showing the presence of a certain amount of nitric oxide.When we considered thatall the carbon dioxide had been displaced, the tap was again turned off and the tube allowed t o remain for 10 minutes. The nitrosyl chloride was then driven out by means of a stream of carbon dioxide into a Varrentrap’s bulb, containing either distilled water or ammonia. When all had been absorbed, the solution was treated as in the former experiments, and the chlorine estimated. Another determination of the temperature mas then made by aspirating dry air through the tube, allowing it to expand, and measuring the residue in the nitro- meter. We found that the temperatures were generally very concor- dant, rarely differing by more than lo”, and often coming within 1 or 2 degrees of each other.Three determinations of the vapour density were made in this way with the furnace at its full heat. The results obtained were 29.73, 29.1, and 29.1. In all these cases we found that the nitrosyl chloride acted on the glass tube forming chlorides of the alkalis. These were volatilised by the great heat, and deposited in the capillary. As the gas was kept passing through the tube for some time, the amount of these chlorides was quite appreciable. We, therefore, made several determinations in the combustion furnace, the gas having previously been liquefied in the tube. This we accomplished by taking a piece of combnstion tubing nearly the same length as the furnace, rounding off one end, and drawing the other out slightly. Three or four cubic centimetres of the chloride were then condensed in the tube, and whilst it was still in the freezing mixture the open end of the tube was drawn out into n very fine capillary; the excess of nitrosyl chloride was allowed t o boil away, then the tube was warmed by placing i t on the bricks over the furnace.A small bulb was fixed on to the capillary to serve as a79 ON NITROSTL CHLORIDE. reservoir, and thus prevent diffusion. pushed straight into the hot furnace, the bed of which was lined with asbestos paper in order t o keep the tube from sticking, and also to facilitate the pulling in and out of the tube. The tube was left in the fiirnace for about a quarter of an hour; the capillary was the11 sealed off and the tube pulled out. TiYlien cool, the end was broken off under water, and from the solution thus obtained the density was calculated by estimating the chlorine in the usual way.The hem- perature was determined both before and after each experiment, by means of air thermometers. These consisted of tubes approximately of the same length as that used for the nitrosyl chloride. They were first thoroughly dried, then pushed into the hot furnace, left for 10 minutes, sealed off, pulled out of the furnace, and, when cool, opened under water. An experiment conducted in this way, with the burners only partly on, gave a mean temperature of 784", and a density of 31-77. Another experiment at 928" gave a result of 29.0. Two more experiments gave the following :- When warm, the tube Xean temperature.. .. 968" V. d. ..... 27.3 *Mean temperature.... 985" V. d. ..... 27.0 This indicates a dissociation of practically 50 per cent. of the nitrosyl chloride molecules at a temperatiire not much below 1000". As we were not able to obtain higher temperatures with the appa- ratus at our command, and using glass tubes, we coiicluded our ex- periments at this stage. The table (p. 80) gives a r6ssurne' of the results of our experiments. From these results, it is evident that nitrosyl chloride behaves in a, very different manner fyom nitrogen dioxide when subjected t o high temperatures. Thus, at 620", a t'emperature at which nitrogen dioxide is completely dissociated, nitrosyl chloride shows not the least trace of dissociation ; and near lOOO", only about 50 per cent. of the molecules are dissociated. This fact would seem to point to a, difference in the constitution of the molecules of the chloride and the oxide of nitrosyl, as nitrogen dioxide may be called.Nitrosyl chloride, in its reactions with water, behaves as the chloride of nitrous acid, and inasmuch as nitrous acid not only forms nitroso-compounds, but by acting on the group ,CH, produces oximes, TCX-OH, nitrous acid would appear to have the formula, - * The following are a few of the results with the air tubes; they show that the (1.) 925.2" (1.) 967" (2.) 930.0" (2.) 969" estimations of temperature were fairly concordant, and may be relied upon :-80 ACTION OF HEAT ON NITROSTL CHLORIDE. Vapour Density of Nifrosyl Chloride between 15" and 985". Met,hod adopted for obtaining bulb full of gas. Passing gas for 45 mins... Liquefying.. ........... ,, .............. ) ) ............. ,) ............. Passing gas.. ........... ,) ............. )) ............. Liquefying ............. ,) ............. , ) ............. Passing gas.. ........... Ziquef ying ............. Passing gas.. ........... ), ............. ,) ............. )) ............. Liquefying ............. )) ............. Bath. ---- Air.. ............ Sulphuric acid ..... >1 1, 7 1 ..... ..... ..... Nethyl salicylate ... Sulphur vapour.. .. >l 7 1 1 1 ..... ..... ..... Combustion furnace Air-bath .......... . . . . . . . . . . . . Combustion furnace Pempera. ture. -- 15" 15 65 11 5 165 222 693 693 693 693 7% 796 815 928 964 965 965 968 985 V. d. (H=l). -- 32.5'7 32 '50 33 *04 32 *50 33 *18 32 -30 32 -90 32.31 33 -24 33 *12 31 -77 31 *36 31 *00 29 -00 29-73 ? 29 *10 ? 29 -10 ? 27 -30 27-00 Per cent.amount of dissociation. 0 0 0 0 0 0 0 0 0 0 8.09 11 -86 15 -17 33 -51 49 '21 51 -97 V. d. calculated for NOCl .................. 32-65. 21-78. V. d. calculated for complete dissociation . . , . O:N*OH, and the chloride therefore O:N-Cl. Now, NOCl is incapable of directly combining wit'h oxygen, and the compound NOzCl seems to have no existence (Williams, Trans., 1886, 49). Hence, we must suppose that that part of the valency of nitrogen which in NO is con- cerned with linking on another atom of oxygen t o form NO, or N,O, (according to temperature) is already occupied by chlorine in NOC1. Since nitric oxide, NO, and nit,rosyl chloride, NOC1, show no ten- dency to polymerise, the union which is est,ablished between NO, and NO, at temperatures below 140" is probably owing to the oxygen. We have been accustomed to regard nitric peroxide as nitroso-nitric anhydride, representing it by the formula O:N.O*K<~, but since the molecules of NO,, concerned in the process of combination, are all alike, an unsymmetrical formula seems improbable. The formula O:N*O*O-N:O seems to satisfy the requirements of the case, as it would account for the format8ioii of nitric, as well as of nitrous, acid by the act'ion of water,CURVE SHOWING VAPOUR DENSITY OF NITROSYL CHLORIDE BETWEEN 600" AND 1000" C. DENSITIES. hARRl5ON L S l N S L l T H 5' MABTIHS. I A N F W rTHE FERMENTATION OF CALCIUM GLYCERATE, ETC. 81 and this leads t o the formula 0:N-O- for the dioxide. This may, perhaps, account for the instability of this oxide at high temperatures by representing it as due t o the unsaturated condition of the oxygen, while the more stable chloride may owe its greater permanence at high temperatures t o the fact that the chlorine is not in the same degree unsatuyated. In conclusion, me have t o thank Dr. Tildec for suggesting the work and supervising most of the experiments. 3Iuson College, Birrning ham.

ISSN:0368-1645    

DOI:10.1039/CT8915900073

出版商:RSC    

年代:1891

数据来源: RSC