摘要:

Mr. Crum on the Oxides of Copper and h a d . 387 CXL'III. On the Action of Bleaching Powder on the SaZts of N February 1843 I read to the Philosophical Society of I Glasgow an account of a rose-coloured oxide of copper which I had obtained by the action of bleaching powder and lime upon nitrate of copper. Although I had then made numerous analysks of this substance prepared under a variety of circumstances I had been unable to obtain from it the full amount of oxygen which a definite compound must contain, and delayed therefore to make it further known until I should have the opportunity of producing it in a purer form. In the mean time the rose-coloured substance was observed and correctly described by Kriiger of Berlin as a combination of the oxide of copper or as he calls it cupric acid with lime.Having corripleted my experiments on this subject as far as my leisure will' permit I shall now state the results I have obtained. When the hydrated oxide of copper is added to a solution of bleaching powder it changes colour and becomes brown. Oxygen gas is then plentifully disengaged and the efferves-cence continues till the whole of the hypochlorite of lime is decomposed. The brown precipitate suffers no change during this decomposition. When separated from the soluble mat-ters it is found to contain no chlorine and no excess of oxygen. I t is anhydrous oxide of copper. Hypochlorite of soda produces the same effect. If we add nitrate of copper to a solution of bleaching pow-der containing a considerable quantity of lime and previously cooled to below the freezing-point of' water a bluish-green precipitate is formed.When the precipitate subsides we find the solution of a fine blue colour and containing copper ; but in what state I have not examined. As the heat advances to the ordinary temperature the copper in solution as well as Copper and Lead. By WALTER CRUM Esq. F.R.S 388 Mr. Crum on the Action of the precipitate changes coloiir nnd both at last become an insoluble purplish black powder. Oxygen gas is disengaged during the latter part of this process and continues for some time to prevent the precipitate from subsiding; but after twenty or twenty-four hours the evolution of gas nearly ceases the particles having united into larger grains sink to to the bottom of the vessel into moderate bulk and may then readily be separated from the soluble matters by repeated mixing with cold lime-water and drawing off the clear liquid with a syphon.The precipitate thus obtained is as I have said nearly black; but by triturating upon a piece of glass it is seen that its real colour is rose-red. Expoaed to the action of boiling water oxygen gas is dis-engaged from this substance and brown anhydrous oxide of copper is left behind. Acids dissolve it with the liberation of oxygen gas mixed with the carbonic acid taken down by the lime. The solution in nitric acid gives n o precipitate with nitrate of silver. Exposed to the air the substance is speedily changed into the green carbonate. In attempting to press and then to dry it in V ~ C ~ C O over sulphuric acid a large proportion was changed into the brown oxide mixed with car-bonate.I t can only therefore be examined in the nioist state and newly prepared. I shall describe the process by which I have obtained the best results. Twenty grains of black oxide of copper prepared by cal-cining the nitrate are dissolved with the assistance of heat in 70 grs. of nitric acid specific gravity 1'35. Fifty grains of fresh hydrate of lime sitied through fine calico are mixed with 1 lb. solution of bleaching powder of specific gravity 1.06, and added to the solution of copper. When the precipitate becomes granular as already described it is quickly washed, and decanted until the lime water comes off nearly pure. The precipitate is then put into a wide tube over mercury an ex-cess of sulphuric acid added to i t ; and after pouring out as much as possible of the solution which is thus formed caustic soda is added to absorb the carbonic acid.In six experi-ments made in this may 20 grs. of oxide of copper produced a compound which yielded of oxygen gas after the necessary corrections,-l*S75 1.886 1 *748 1 *915 1 *795 1'747 Mean . . 1.828 grain Bleaching Powder on the Salts of Copper am€ Lend. 389 By calculation 20 grains CiiO changed into Cu O3 ought to yield by Berzelius's numbers 1-98 grain of oxygen. A nearer approximation than in the foregoing results is scarcely to be expected'; for although there was no perceptible ttis-engagement of gas during the washing of the precipitate in these experiments it is certain that oxygen always escapes during the time so employed.The quantity of lime necessary to the production and sta-bility ofthis oxide is not more than 1 equivalent after satura-tion of the nitric acid 1 atom of lime to 3 of copper gave only 0.558 gr. of oxygen gas instead of the mean quantity of 1.828 ; 2 atoms to 3 of copper yielded 1-295. 1 conceive the rose-coloured powder then to be a compound of an oxide of copper with lime in which the copper exists in the state of sesquioxide Cu 0,. I have not succeeded in producing this oxide by means of the hypochlorites of potash or soda even with the alkali i n great excess; but by adding caustic soda to a solution of hy-pochlorite of lime and afterwards nitrate of copper we obtain the calcareous compound (lime being precipitated along with the copper) in a state of division so fine as to show the rose colour as soon as it is formed.This method however does not serve for the purposes of analysis for the powder never becomes granular and remains therefore too bulky to be washed . I t will now be observed that the dehydrating action of the hypochlorites upon oxide of copper must depend upon the momentary formation of a sesqiiioxide in which the oxygen has replaced the previously combined water. The solution of bleaching powder in which the sesquioxide has been formed is of a fine hut very pale pink colour anti contains so small a proportion of the colouring ingredient, that the nature of that body can scarcely be discovered by analytical means.The second washing of the oxide is colour-less; but if a very minute portion o f sulphate of manganese be added the pink colour is restored. When manganate of potash is dropped into nitric acid the well-known red colour of hypermanganic acid is produced. I n lime water the colour is bluish green; but in bleaching liquor even with excess of lime we have the peculiar aniethystine colour of the solution in which the sesquioxide of copper has been p d u c e d . Bleaching powder has long been said to contain manganese, and to this I at first attributed the pink colour of the original solution; but I afterwards found that it could be reproduced from pure Irish limestone which I employed. Even marble gives a pink solution in the same circumstances 390 Mr.Csuni on the Oxides of Copper and Lead. The vessel in which the sesquioxide has been produced, is lined with a beautiful rose-coloured deposit which remains attached to the glass wheii the other matters are washed out; but it fades away in a few hours particularly when exposed to light and cannot even be long preserved in the solution which forms it. Dissolved in dilute nitric acid copper is found in the solution and no manganese. There can be no doubt that like the precipitate it is the sesquioxide of cop-per in combination with lime. The red oxide of iron has also the power of decomposing the hypochlorites. This fact as well as the formation of a superoxide of copper was observed many years ago by Mr. Mercer of Oakenshaw and stated by him to the British Association in 1842 in a paper containing some interesting speculations on these and other weak affinities which give rise to many of the phzenomena of catalysis.When a solution of bleaching powder is mixed with nitrate of copper a light bluish-green powder precipitates the bulki-ness of which renders it somewhat difficult to wash. This powder is very slightly soluble in water and scarcely changes colour in boiling. Heated in a glass tube over a spirit-lamp, chloride of copper sublimes into a cooler part of the tube and water escapes. The residue consists of black oxide of copper mixed with a quantity of chloride which may be separated from the oxide by washing. Professor Graham who sug-gested to me this experiment remarked the analogous effect of boiling water in separating water from a hydrate.I t proved to be a hydrated oxichloride of copper the substance known by the name of Brunswick green and formed in a variety of other circumstances. Analysis gave. me nearer 3c110 Cu Cl than 4Cu 0 Cu Cl; but the presence of car-bonate in the specimen left me in doubt upon this point and 1 could riot resume the inquiry. In this reaction the whole of the hypochlorous acid is set fiee. 4(CuO NO,) + 3 ( C a 0 ClO CaC1) =4(Ca0 NO5) + 3Cu0 CuC1+ 2CnC1 + 3C10. Peroxide of lead is often produced by passing a stream of chlorine through a solution of sugar of lead. The chloride which accompanies it in tbis way may be also converted into peroxide by employing a solution of bleaching powder instead ofchlorine. The peroxide produced by these means has a light brown colour although washed with dilute nitric acid and boiling water.I have succeeded by the following pro-cess in forming a compound nearly colourless of peroxide of Zead and Ziwe. Dissolve in water 1 lb. of nitsate of lead Mr. Crum ON the Oxides of Copper and Lead. 391 and add it along with 3 equivs. of lime to 16 pounds of a so-lution of bleaching powder of sp gr. 1-08. Heat the mixture gradually to 160' Fahr. and stir it frequently during five hours. Pour off the clear liquid add 16 pounds more of the same solution and continue the heat three hours longer. The combination is obtained white with oiily a slight brown tinge. It is quite insoluble in water and when dried does not alter in the air. Nitric acid by dissolving the lime leaves the peroxide of a deep black colour and therefore much deeper than that obtained by any of the processes usually employed.I have had no means of determining the proportion of lime coiitained in this plumbate. With less than two equivalents to one of oxide the compound is not white; and 5\11 excess of lime cannot afterwards be dissolved away by an acid without discolouring the salt. I found it convenient in these experiments to prepare a quantity of cream of lime by dropping newly-burnt lime into boiling water stirring up allowing the sand and the grosser parts to subside and pouring off the superstratum. When this again had subsided for some time the water was poured away and the cream of lime which remained corked up in smaill bottles for use. By this means I had always at hand a quick lime whose equivalent I knew free from sand and free from carbonate. Marble of course answers the best for this purpose. Manganese again appears in the nitric acid which has been employed to decompose the plumbate in the state of a pink-coloured hypermanganic acid. When this solution is poured off and more water and nitric acid added to the peroxide that is left a small quantity of sulphate of manganese restores the colour. Peroxide of lead prepared by the same or by other means when dried does not yield the pink colour without the application of heat

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DOI:10.1039/MP8430200387

出版商:RSC    

年代:1843

数据来源: RSC

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Mr. Crum ON the Oxides of Copper and Lead. 391 May 5 1845.-The President in the Chair. Thomas Dell Esq. was elected a Member of the Society. The following papers were read :-An abstract from a Letter from Professor Bunsen of Marburg, stating that he had undertaken some experiments on the direct for-mation of cyanogen from the union of the nitrogen of the air with carbon. Two experiments were made with carbonate of potash and charcoal from pure sugar in iron tubes heated to whiteness through one of which nitrogen was led through the other carbonic acid. In the first experiment there was a yellow-red flame on igniting the gases and which smelt strongly of cyanogen ; there was also abun-dant vapours of cyanide of potassium the contents of the tube gave Cdem. SOC. Mem.VOL. II. 21 392 Prof. Graham OTL Phosphoric Acid in Wafer. upwards of 6 grarnmes of cyanide of silver free from chloride. In the second tube the gases were perfectly free from cyanogen burnt with a pale blue flame and no cyanide of potae'sium could be de-tected in the mixture. The reason of previous failurea was the absence of a sufficiently intense heat. CXLIV. Note on the Existence of Phosphoric Acid in the Deep-WelL Waler of the London Basin. By THOMAS GRAHAM Esq. P.B.S. T H I S water is obtained on piercing the London clay which forms an inipervions bed generally exceeding ZOO feet in thickness and flows from fissures in the subjacent chalk. It is always highly soft and alkaline and remarkable for the predominance of soda salts over earthy salts among its solid constituents.I have never found it to contain a sensible quan-tity of potash although salts of the vegetable alkali appear among the constituents of the water of the deep Artesian well of Grenelle. When evaporated .considerably a small deposit takes place in the London deep-well water which consists chiefly of car-bonate and phosphate of lime. The remaining liquid gives with nitrate of silver a precipitate of chloride and carbonate of silver which is white without any shade of yellow ; but if t i portion of the wnter amounting to an ounce or two be eva-pornted to dryness in a pltttinuni capsule without removing the precipitate and the heat afterwards continued so ns to raise the temperature of the resulting dry saline matter to low redness then on redissolving by distilled water and adding nitrate of silver a precipitate is obtained in which the yellow colour of the phosphate of silver is very perceptible.The earthy phosphate is decomposed by ignition with the alkaline belonging to the water and the soluble phosphate of soda is produced. The following are the results of the analysis of the water from the deep well in the Brewery of Messrs. Combe and De-lafield Long Acre. An imperial gallon of the water con-..tined 56.45 grains of solid matter 100 parts of which gave-Carbonate of soda . . . . . Sulphate of soda . . . . . Chloride of sodium . . . . . Carbonate of lime . . . . . Carbonste of magnesia . . . . Phosphate oflinie . . . . Phosphate ofiron . . . . . Silica . . . . . . . . . . 20*70 42.94 22-58 10-96 1-92 034 0-43 0.79 1 O0*6 Mr. De la Rue on a CrystalZized A h y of Zinc. 393 The growth of green confervte in this water is extremely rapid and occtrsions inconvenience when the water is kept in open tanks. It is a subject perhaps worthy of inquiry whe-ther the value of some waters for irrigation may not depend upon their containing phosphoric acid this constituent having hitherto been generally overlooked in waters

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DOI:10.1039/MP8430200391

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年代:1843

数据来源: RSC

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Mr. De la Rue on a Crystallixerl AIloy of Zinc. 393 CXLV. Orb a Cyysfallired Alloy of Zinc Iron Lead and Copper. By WARREN DE LA KUE ESP. alloy in question was obtained from the worn-out the mercury had been recovered by distillation. As the sul-phate of zinc resulting from the solution of the zinc in the battery is exceedingly pure it follows that the residue of the plates contains besides the mercury used for amalgamation, most of the impurities contained originally in the whole plates, and the metal obtained therefrom is consequently much infe-rior in quality to the original rolled zinc. Zinc in a fit state for rolling is obtained by running off the fluid portion from a mass of cast zinc which has been allowed to cool down to R certain point after fusion the metal left be-hind being less pure than that which flows off.The manu-facturer who furnishes me with rolled zinc and takes hack the zinc obtained horn the worn-out plates informed me that the latter is unprofitable to re-work from its leaving an unusually large residue in refining ; this statement induced me to inves-tigate the coniposition of this residue and I proceeded in the following manner. About 2% pounds of worn-out plates being introduced into an iron pot and the mercury distilled off by heating it to redness, the fused metal was fined by adding a quantity of tallow and stirring well ; after the oxide bad been withdrawn the metal was removed to another vessel to cool ; it weighed about 15 Ibs. When partially solidified the fluid portion was drained 0% leaving a considerable portion of the metal in a spongy state, mid occupying the same bulk as the whole mass; one part of zinc plate residues usually gives the following results :-Zinc.. . . . . *673 Mercury . . . . '043 Dross and loss . . -284 THE amalgamated 5nc plates used in the voltaic battery after 1'000 this average being taken on a quantity of old plates amounting to 2; hundred weight. The spoiigy residue examined with the microscope under tt power of twenty to fifty times linear proved to be composed 2 D 994 Mr. De la Rue on a Crystallized Alloy of Zinc, of minute perfectly clean and well-formed crystals of the form of right rhombic prisms; their breadth varying from the &th to &@ of an inch ; the angles of the base are of about 1 19' and 6 1 respectively.A selected portion free from scoria weighing 5 grammes, was subjected to analysis and found to be an alloy of zinc, iron lend and copper. After solution in nitric acid the lead was separated as sulphate which weighed *441 grm. The copper being precipitated by sulphuretted hydrogen and then converted into oxide weighed 009 gramme. The iron being thrown down as succinate fi-om the neutralized solu-tion and after the removal of the soluble salts washed with ammonia and ignited there resulted '1847 gramme of per-oxide of iron. The zinc precipitated by carbonate of soda gave when ignited 6'6213 grammes of oxide of zinc. 'l'hese results give the following composition of the alloy :-Grammes. Per cent. Zinc . . . . . . . 4.500 = 90' Iron .. . . . . . 0128 = 2.56 Lead. . . . . . . * S O 0 = 6-Copper . . . . . . *072 = 1'44 5'000 100'00 These quantities agree very exactly with the following mula :-Per cent. Per cetit. Calculated. Found. 240 Zn = 89-99 90. 8 Fe = 2-52 2-56 5 Pb = 6.02 6' 4 c u = 1.47 1 '44 for-I t is possible that these substsnces may be combined into proximate constituents and the alloy be a compound of these, but we have no data for so grouping them. On re-melting, however a portion of these crystals the mass separated into two portions,-a metal considerably niore fluid and a com-pound more infusible than the crystals; these I have not examined. From the preceding analysis it will be seen that a portion of alloy amounting to but 10 per cent. is capable of retaining in combination 90 per cent.of zinc this will account for the large portion of difficultly fusible metal in a pasty state which frequently rises to the top of the melting-pot in fusing corn-niercial zinc and which is probably an alloy of zinc combined with but n small portion of other metals Mr. Williamson on Ozone. 395 May 17 1845.-The President in the Chair. Mr. Button presented a specimen of rectified Rangoon Naphtha, Mr. De la Rue presented a specimen of the Alloy of Zinc &c. the The following papers were read :-and an oily fluid obtained during the process of its rectification. subject of the communication read at the previous Meeting. CXLVI. Some Experiments on Ozon~. By A. W. WILLIAMSON Esq. T has been satisfactorily proved by Marignacs that the I pliaenomena attributed to ozone have no connexion with the presence of nitrogen.H e finds that the ozone odour may be developed in liquids free from nitrogen as well as in those which contain that element H e decomposed by the voltaic current a portion of water from which atmospheric air was carefully excluded and found that the peculiar smell of ozone was given off as abundantly after ti continuance of the action for several days when a qiiarter of the liquid had disappeared in the form of gas a s at the beginning of the decomposition. Marignac'confirms Schonbein's statement that the odorous matter in air acted upon by phosphorus is identical with that present in the oxygen set free by the electrolytical decompo-sition of water; and indeed recommends as the most con-venient way of preparing ozone to pass atmospheric air over phosphorus.The substance made use of in his researches was thus prepared. The object of' the experiments I am about to describe was to obtain some explanation of the phenomena which give rise to the supposition ofthe existence of such a body as ozone. The poles of a Bunsen's battery consisting of four elements, were plunged into sulpliuric acid diluted with three volumes of water. The hydrogen from the copper plate at which it was evolved was allowed to escape into the atmosphere. The oxygen which was evolved upon a plate of platinum was col-lected in a small tubulated glass bell placed over it anti two-thirds sunk in the liquid. Heiice it was conveyed into a tube filled with chloride of calcium through which it passed with-out any diminution of its peculiar smell. The oxygen thus dried was conducted into a glass tube filled with copper turn-ings and heated to redness. At the further end of this tube, which was kept cool globules of water soon made their a p pearance which on being removed were speedily reproduced, and continued increasing so long as the process lasted. The oxygen on entering the tube full of copper being quite dry, * Comptes Rendus ri I'dcadfmie Mars 1845

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DOI:10.1039/MP8430200393

出版商:RSC    

年代:1843

数据来源: RSC

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Mr. Williamson on Ozone. 395 May 17 1845.-The President in the Chair. Mr. Button presented a specimen of rectified Rangoon Naphtha, Mr. De la Rue presented a specimen of the Alloy of Zinc &c. the The following papers were read :-and an oily fluid obtained during the process of its rectification. subject of the communication read at the previous Meeting. CXLVI. Some Experiments on Ozon~. By A. W. WILLIAMSON Esq. T has been satisfactorily proved by Marignacs that the I pliaenomena attributed to ozone have no connexion with the presence of nitrogen. H e finds that the ozone odour may be developed in liquids free from nitrogen as well as in those which contain that element H e decomposed by the voltaic current a portion of water from which atmospheric air was carefully excluded and found that the peculiar smell of ozone was given off as abundantly after ti continuance of the action for several days when a qiiarter of the liquid had disappeared in the form of gas a s at the beginning of the decomposition.Marignac'confirms Schonbein's statement that the odorous matter in air acted upon by phosphorus is identical with that present in the oxygen set free by the electrolytical decompo-sition of water; and indeed recommends as the most con-venient way of preparing ozone to pass atmospheric air over phosphorus. The substance made use of in his researches was thus prepared. The object of' the experiments I am about to describe was to obtain some explanation of the phenomena which give rise to the supposition ofthe existence of such a body as ozone.The poles of a Bunsen's battery consisting of four elements, were plunged into sulpliuric acid diluted with three volumes of water. The hydrogen from the copper plate at which it was evolved was allowed to escape into the atmosphere. The oxygen which was evolved upon a plate of platinum was col-lected in a small tubulated glass bell placed over it anti two-thirds sunk in the liquid. Heiice it was conveyed into a tube filled with chloride of calcium through which it passed with-out any diminution of its peculiar smell. The oxygen thus dried was conducted into a glass tube filled with copper turn-ings and heated to redness. At the further end of this tube, which was kept cool globules of water soon made their a p pearance which on being removed were speedily reproduced, and continued increasing so long as the process lasted.The oxygen on entering the tube full of copper being quite dry, * Comptes Rendus ri I'dcadfmie Mars 1845 396 Mr. Williamson on Ozone. it thus appears that water is formed by the reducing action of the heated metal. I n the manner of performing this experiment there are two circumstaiices which take from the result the certainty of cor-rectness necessary fbr drawing conclusions. These circum-stances are the following :-1st. The copper turnings having by heating to redness in the air been covered with a coating of oxide were reduced by means of a current of hydrogen p s and although the ex-cess of that gas had been removed as fm RS possible by a cur-rent of dry atmospheric air yet it was possible that some hydrogen might adhere to the porous copper which would account for the formation of water on oxygen being brought to the hydrogen at a red heat.2nd. Hydrogen being somewhat soluble in water the oxy-gen may in passing through the liquid have taken up some traces of that element and on coming in contact with the heated metal the two gases wouId combine. To obviate the first of these objections the oxidated copper was reduced by a current of dry carbonic oxide gas pnd to re-move the possibility of free hydrogen being carried over with the oxygen the latter was passed through a tube filled with spongy platinum and then again over chloride of calcium. It was however found that the substance producing the peculiar odour was either deconiposed or absorbed by the platinum, none of it passing over.The difficulty was at length avoided by evolving the oxygen from a liquid in the deconiposition.of which no hydrogen is set free. Oxide of copper dissolved in sulphuric acid was decomposed instead of water. The oxygen then evolved pos-sessed precisely the same odour as that fiom acidulated water, and after careful drying was conducted into the heated tube containing copper turnings reduced by carbonic oxide. Water speedily appeared at the cool end of the tube and the quantity continued increasing as long as the process lasted. I n subsequent experiments oxygen prepared in the manner just described was dried and passed through a sm-all glass tube heated to redness by a spirit-lamp; on coming out of which it had completely lost all odour.At the end of this tube a chloride of calcium tube was then fixed which had been accu-ra tely weighed. After the oxygen was conducted for a short time through the heated tube the chloride of calcium tube was found to have increased perceptibly in weight. Water through which oxygen charged with ozone was at-lowed to pass assumed the odoiir of it. When this solution o Mr. Williamson on Ozone. 397 ozone WRS added to a solution of iodide of potassium and starch a pale blue colour was produced; ferro-cyanide of potassium containing ozone gave a blue precipitate with a proto-salt of iron. Lime water formed with the solution of ozone a heavy and apparently crystalline precipitate. Baryta water behaved in a similar manner.The liquid after the pre-cipitation gave no reaction with iodide of potassium and starch ; but on an acid being added a blue colour immediately ~ p -peared. Oxygen charged with ozone was next passed through a tube surrounded by R frigoric mixture consisting of chloride of cal-ciJm and snow; but nothing perceptible was deposited. The following experiments were made for the purpose of ascertaining whether as has been assumed the substance causing the ozone odour is also produced by the action of phosphorus on atmospheric air. Through a glass. tube filled with pieces of phosphorus a current of moist atmospheric air was driven by means of a gasometer; it assumed the peculiar odour so well known to acconpany phosphorus. Water througli which this air was then allowed to pass for a considerable time remained inodo-rous gave not the slightest reaction with iodide of potassium and sarch left ferro-cyanide of potassium unchanged and gave dl the reactionp of a dilute solution of phosphoric acid, On Wepeating this experiment it was performed in a some-what different manner.The air which had passed over phos-phorus was allowed to pass directly into the iodide and starch,and a deep blue reaction soon ensued in that part of the liqud on which the bubbles in passing through first acted ; and wa; increased in a greater proportion to the air passing througl when a rapid current of air was driven over the phosptiorus instead of a slow one. On again as in the tornier nstance passing the air through water and then treat-ing the atter with iodide of potassium and starch no reaction was obbined.We have here an evident difference between the rea:tions of the su~stance contained in the electrolytic oxygen a i d that produced by the tiction of phosphorus on ntmospleric air. T o what then is to be attributed the resction producctl by the direct action of air psssetl over phosphorus on iodde of potassium and starch ? l h e following experi-ment vas made. I n a lorig and wide tube loose pieces of astlestas and pieces of phosphorus were placed alternately. By heiting the tube thus filled the phosphorus was partly melted into the asbestos anti partly sublimed upon it ; thus exposiig a far greater surface than in the former experiments. Aft< the tube had completely cooled atmospheric 9' ir was The odour did not reappear 398 Mr.Williamson on Ozo?re. driven through it into the iodide and starch but not the slightest reaction was produced. This result plainly indicates the cause of the reaction in the preceding instance. The phosphorus was there unable for want of sufficient surface to absorb all the oxygen of the air passing over it. A mixture of phosphoric acid and oxygen therefore went over and by their simultaneous action on the iodide of potassium set iodine free. As soon as a sufficient surface was given to the phosphorus all oxy en was absorbed, phosphoric acid was alone carried over by t a e nitrogen and the iodide was decomposed in a different manner. Lime water through which the air thus treated with phor-phorus was passed deposited a voluminous sediment consist-ing of' phosphate of lime.This liquid cleared by a few drcps of acid remained afterwards unclouded on being heated with chloride of niercury it consequently contained no phospho-rous acid. With iodide and starch it gave no reaction eiher alone or after an acid was added to it. These experiments appear to me to show,-I. That the peculiar properties belonging to the oxygen set free by the agency of the electric current are produced by the admixture of a peroxide or acid of hydrogen ; 11. That by the action of phosphorus on atmospheiic air the same substance is not produced. That this compound of hydrogen and oxygen is not idcntica1 with Thbnard's peroxide would appear from the fact of its being volatile and odorous properties which the othtr does not possess.I have repeatedly prepared Thhard's pcroxide of hydrogen by decomposing peroxide of barium with d fferent acids for the purpose of satisfying myself whether it ever possesses odour but' have always obtained R negative result. The oxygen disengaged from it by the action ofpercnride of nian5aiiese is as inodorous as the liquid itself. The Dxygen obtained by the electrolytical decomposition of an queous solution of peroxide of hydrogen possesses the same odour, only apparently in a somewhat greater degree as thit fiom water. The bleaching action which the substance contained n elec-trolytical oxygen produces when dry on litmus paper i; a fact which of itself indicates that it must be a peroxide. Itis well known that chlorine does not possess that property blt only such combinations of oxygen as give up this elemert with great ease as for instance hypochlorous acid. I cannot conclude this notice without expressing the obliga-tion I am under to Professors Liebig and Buff for thei kind direction and assistance during these experiments

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DOI:10.1039/MP8430200395

出版商:RSC    

年代:1843

数据来源: RSC

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[ 399 3 CXLVII. On the Solubility of Oxideof Lead ia Perre Water. By LieutXol. PHILIP YORKE. I N the Philosophical Magazine for August 1834 I published Some of the principal results contained in it were confirmed by Bons-dorff in two papers; he found that 7000 parts of pure water free from access of carbonic acid dissolved one of oxide of lead; my experiments gave &oth to k 0 t h . Since that. time two papers have appeared on the same suhject one by Dr. Christison” and oiie by Mr. R. Phillips Jun.? The last-named chemist considers that the oxide of lead is not dis-solved but merely mechanically suspended in the water be-cause the liquid is deprived of the lead by passing it through a paper filter. It is to this opinion that I propose to direct attention in the present notice.The fact that the aqueous solution of oxide of lead would not pass through a .filter was noticed by me in the paper al-ready referred to; but as the action of tests on the liquid was just what one observes with solutions; as no time allowed for subsidence made any difference in these appearances ; as the liquid deposited crystals of oxide of lead not only on the lead but on other bodies; as when decomposed by the voltaic bat-tery it gave metallic lead at the negative pole and peroxide at the positive; I did not consider that the stoppage of the oxide of lead by the filter was any proof of its not being dis-solved. There still however remains this question to be an-swered,-In what way does the paper act in retaining the ox-ide? and 1 think that the followirig experiments afford an answer to the question.I placed some clean rods of lead in bottles of distilled water loosely stopped ; in this way after removing the rods of lead, I obtained a clear liquid which when tested by sulphuretted hydrogen gave a deep brown colour. Ort passing this liquid through a double filter which had been previotisly washed with hot distilled water it appeared to be very nearly deprived of lead when two or three fluid ounces had passed through, the filters were removed washed then iinmersed in a solution of sulphuretted hydrogen again washed arid dried. Some torn fragments of the filters were then mounted in Canada balsam tbr examination by the niicroscope. On examination with powers of from 150 to 400 the fibres of the flax corn-posing the paper were seen to be browned and in many in-stances it could be distinctly observed that the colouring sub-a paper on the action of water and air on lead.* Transsctions of the Royal Society of Edinburgh. + Pharmaceutical Journal for December 1844 400 stance occupied the interior of the tubular fibre. Now it is stated by Mr. Crum in the Philosophical Magazine for April 1844 that cotton wool possesses the power of abstracting the oxide of lead from its solution in lime-water and that this property is made available in the processes for dyeing cotton with the chrotnates. I found that on filtering a solntion of oxide of lead in lime water through a triple filter that whereas the original solution gave a deep black when tested by sol-phuretted hydrogen the filtered li;luid gave but a pale brown ; and it required that the unfiltered liquid should be diluted with thirty times its volume of water to produce the same test as the; filtered.I then tried the effect of mere immersion of the paper in the aqueous solutions before used. A bit of filtering-paper ten inches by two inches was boiled in distilled water and then put into an ounce phial filled with the aqueous solution ; after remaining six hours the liquid was poured off sod tested it give a pale brown and it required that the liquid which liacl not been in contact with the paper should be diluted with ten times its volume of water to produce the same tint. This ex-periment was repeated with a stronger solution of oxide of lead in water the water was poured off at the end of four hours; it then gave a pale brown and it required that the original liquid should be diluted with four times its bulk of water to produce the sanie tint.A fresh portion of the same solution was then poured on the same paper and left for a night; then on testing the liquid g a v e it brown tint barely perceptible and it required that the original liquid should be diluted with from fifteen to twenty times its volume of water to produce the same. From these experiments it is clear that the effect in ques-tion is dependent on a power possessed by the paper in com-mon with several other porous bodies and organised fibres, of separating certain substances from their solutions a power sufficiently well known though little understood *.I n consi-dering this view of the subject in the present instance there is a circumstance of some practical importance which it would appear ought to follow viz. that after the fibres of the paper had been saturated with the oxide of lead then this substance should pass through in solution. To ascertain whether this was the case I made the following experiments. J obtained a strong aqueous solution of oxide of lead by immersing slips of clean lead in about three quarts of distilled * Tlie effective filter mentioned in Dr. Clark's Notice page 384 is formed of well-washed sand and has been in use during twelve months without any apparent diminution of power. Col. Yorke on the Solirbility Ofthe Oxide $Lead Messrs. Playfiiir and Joule on A!omic Volume &c.401 water contained in a two-necked bottle throu rh which oxygen gas was passed and maintained in contact wit\ under a slight pressure. In this manner I procured a solution which when quite clear yielded &Gtb of' ignited oxide of lead. A filter of paper rather less than &th of an inch thick and four inches in dianieter was prepared and washed; then by fitting into one of the two necks of' the bottle a siphon with equa1 legs, so as to resemble Gay-Lussac's apparatus for washing filters (except that I used a contrivance to prevent the necessity of the air supplied to bottle from bubbling through the solutioii), I was enabled to allow the filtration to go on with coiisider-able regularity for ninny hours. 'l'he fii-st portion of licjuid which passed through gnve R pale brown when tested; \vhen nine Auid ounces had passed through the effect was the same as at first and a portion ( 0 ) was reserved for future com-parison.IQhen forty fluid ounces had passed through the liquid which was quite clear gave a niuch darker tint with the test than any wliicti had previously been obtained in the experiment. I t gave a tint about equal to that given with the unfiltered liquid when diluted with its ow11 volume of water; while it (i. e. the last filtered portion) required to be diluted with twice its yoluriie of water to produce the same tint as that given by the reses ved filtered portion (a). 'The liquid now passed through the filter very slowly; it was tested again, when eight more fluid ounces had passed through with the same result as before except that the tint was a trifle darker. This experiment sufficiently shows that the effect contem-plated does occur :in(! that it would be unsafe to trust to the action of a filter to separate oxide of lead from water for an unlimited time

ISSN:0094-2405    

DOI:10.1039/MP8430200399

出版商:RSC    

年代:1843

数据来源: RSC

摘要:

Messrs. Playfiiir and Joule on A!omic Yulume &c. 401 CXLVII I. On Atomic Volume and Specgc Gravity. B’ LYON PLAYFAIR Esq. Ph.D. and J. 1’. JOULE Esq. SECTION I. T H E discovery of Gay-Lussac that gaseous bodies com-bine in equal or in iiiiiltiple volumes and that theresult-ing compounds stand in a similar simple relation to their con-stituents is one of‘ the most important discoveries ever made in physicnl science. Its utility has been diminished by its supposed innpplicability to liquid and solid bodies as its own exactitude at different temperatures is entirely owing to the equal expansibility of the same volumes of different gases by equal increments of heat. In its most simple form therefiue i t was ci qwiori impro 240 Messrs Flayfair and Joule on bable that the law of Gay-Lussac should apply to the liquid and solid forms of matter.But as the larger number of sub-stances are either liquid or solid and incapable of passing into the gaseous state even at very high temperatures the im-portance of discovering the law which governs the volumes of these forms of niatter has long been recognised and for some time past has much enaaged the attention of philosopliers. The first cheniist wto drew attention to this subject was Dr. Thomson who published a Table* in the year 1831 of the specific volumes of certain of the metals obtained by di-viding their atomic weights by their specific gravities. In this table a remarkable coincidence of volume is observed in several of the metals most nearly allied in chemical characters.More recently the subject has been 'examined in detail by Kopp Schroder and Persoz whose researches have thrown considerable light on this obscure department of physics. Koppt drew attention to the circumstance that in many cases isomorphous bodies possess the same atomic volume, the law being correct when the isomorphism is strictly accu-.rate but approximating only when this is not the case. H e admits also that perfect equality of the volume exists only at particular temperatures on account of the unequal expansion of isomorphous crystals. Schroder 1 made the interesting observation that the re-mainder is the same when the primitive volume of the corre-sponding member of a series of analogous compounds is sub-tracted from them ; thus AO BO and CO leave a constant remainder when the known volumes of A B and C are sub-tracted respectively from the known atomic volumes of the compounds.Koppg confirms this discovery to a certain extent belie-ving however that the primitive volumes A B and C must be assumed in certain classes of salts to be different when in com-bination with 0 from their volumes when isolated. H e also announces the discovery 11 of a great regularity in the physical properties of analogous organic compounds so much so that the study of the physical characters of the compounds of one body enables us to predicate those of the corresponding coni-pounds of another substance. The discoveries of Schroder and Kopp with regard to * Chemistry of Inorganic Bodies vol. i. p. 14. f Poggendorff s Annalen Band xlvii.; and Annnlen der Chenaie Band 1 Poggendorff's Annaden Band 1. S. 554. 0 Ueber das Specij%csds Gewicht der Chentischen Verbinndungen. ]I An?zaZen dcr Cheniie Band xli. S. 79. xxxvi. S. 1. Frank-fort 1841 Aimic l7obme and Spec$c Gravity. 403 the atomic volumes of liquid and solid bodies do not except in a very few instances indicate an approach to a simple mul-tiple ratio of volumes and are therefore only in a small de-gree connected with the law of gaseous volume. W e there-fore thought it desirable to enter into a series of inquiries on this most important subject and we have now the honour to lay before the Society the First Part of these researches. Hitherto the inquiry has been principally confined to solid bodies on the just ground that their diminished rate of ex-pansion offers less difficulty to the discovery of the law regu-lating volumes.But there is an objection to the use of so-lids which to a certain extent counterbalances this advantage, viz. that tbey do not present matter in a perfectly uniform condition free from cohesion. On consideration therefore we were led to believe this objection to be so powerful that we conceived it to be preferable so to separate the particles of the body under examination as to destroy their cohesion, without at the same time altering their chemical properties. Solution in water was the obvious means O f effecting this purpose according to the notions generally entertained of so-lution and it was therefore resolved to experiment princi-pally upon soluble bodies of well-known and defined constitu-tion.At the same time it was necessary to examine the re-lation of the solid volume to the volume of the body when in solution so as to indicate the connection between the solid and the liquid atom. The specific gravities of salts are little known and even when recorded are described so differently by different ob-servers that it was necessary to determine the specific gravity in each of the cases upon which the experiments were insti-tuted. Hitherto the volumes of solids had always been r e ferred to an equal volume of water; in other words the soEid form of matter had been referred to its liquid form. This dif-ference of conditions was no small impediment to the discovery of a law which might be modified for each form of matter".By determining the volume of the substance in solution we compared it in its liquid state to the liquid form of matter in * Before leaving the notice of the labours of those who have preceded u5 in inquiring into the nature of specific gravity we must not omit to no-tice the speculations of the ingenious Persoz who (in vol. xl. of the Ann. de Ch. et de Phys. p. 119) drew attention to the equality in volume of isomorphous bodies and even of some which were not isomorphous. Persoz also believes that the volumes of all bodies are multiples of 56 or half the atomic weight of water; but this idea does not agree with recorded observations and is directly contradicted by accurate estimations of spe-cific gravities.-See the work of M.Persoz Introduction Ci I'Etude de la Chinaie MoKculaire page 834 et aeq 404 Messrs. Playfair a d Joule on which it was dissolved ; and by contrasting the volume of the solids with each other and also with their volume when ren-dered liquid by water we conceived that we niight be placed in more favourable conditions for elucidating a law. Bishop Watson* was the first chemist who endeavoured to estimate the increase of volume when salts dissolve in water ; for although both Gassendust and the Abbe Nollett had written and Ellis§ had experimented upon the same subject, they had artived at conclusions entirely erroneous which were removed by Watson’s more accurate experiments. Watson’s apparatus was rude enough beinfi a matrass capable of hold-ing 67 ounces of water into which he projected 24 penny-weights of each of the salts upon which he experimented and noted the rise iri the neck of the matrass.He completely ex-ploded however the idea that saline substances dissolve in water without increasing its bulk. Between the time of Bishop Watson whose investigations on this subject are most profound when we consider the period at which he wrote and that of Dalton there were no labourers in this field to whom we need draw especial atten-tion. I n the year 1840 Dalton11 made the interesting dis-covery that sugar and certain salts on being dissolved in water increase its bulk only by the amount of water pre-exist-ing in them. He generalized this observation by assert-ing that all hydrated salts dissolve in water increasing its bulk merely by their amount of water of hydration while anhy-drous salts do not at all increase the bulk of the water 111 which they are dissolved.But it must not be forgotten that when Dalton published this paper he was much enfeebled by illiiess and 011 this account it does not derogate from the acuteness of the phi-losopher that Mr. Holker was unable to confirm Dalton’s results in repeating the experiments in 1843**. He did so, however in the case of sulphate of magnesia and approxi-matively in that of one or two other salts. As Mr. Holker’s paper has not been published we are unable to state his claims in the progress of this subject; but we believe that an attempt was made to show a multiple relation in the increnients of isomorphous salts although his experiments were conducted Philosophical Transactions 1770.f Gass. Yhyr. lib. i. sect. 1. cap. 3. $ Lpns de Physique vol. iv. 11 ‘‘ On the qiiantity of Acids Bases and Waters in Salts and a new mode of measuring them,” read to the Manchester Literary and Philosophical Society 6th October 1840 and published as a pamphlet. ** Paper read to the Manchester Literary and I’hilosophical Society but not pitblished. Berlin Memoirs 1750 Atomic Volume and Speczjfc Gravify. 40 5 wittiout reference to the density or temperature of the solu-tion on which he operated. was occasioned by the moistening of the tube during the time it was in the reclining pos-ture for the precaution was always taken to moisten the walls of the tube previous to the 'In the experiments about to be described, the apparatiis for estimating the volume of bodies when dissolved consisted of a glass bulb to which a stem was attached.The bulbs varied in capacity from 1000 to 4000 grains of water and the diameter of the steni was from one-eighth to one-sixteenth of an inch according to the character of the ex-periment. In the bulbs employed for ordi-nary purposes each grain of water occupied about a quarter of an inch in the stem and as the graduation was made in grains of water at 60° the experimeiit could be made to the tenth of a grain of increase in volume. I n every case care was taken that the salts used were rigidly pure and in their proper state or hydration. The distilled water employed to dissolve them was deprived of air by long-continued boiling arid preserved for use in stoppered bottles.The salt was introduced by a tuliulure in the side of the bulb in the following manner. The bulb was filled with water until it reached a fixed point in the stem when it was reclined and the stopper removed. A weighed quantity of salt was then introduceci by a dry funnel and the stopper reinserted care being taken that no air was admitted during the operation; the increase in the stern after the salt was dis-solved gave the volume of the quantity of salt used in the experiment. I t was found by repeated trials that no loss of volume or error experiment. It is evident that the volume ociupied by a salt in solution must be modified by the position of the point of its maximum density.Despretz has shown * that the tempera-ture at which solutions are most dense becomes lower in pro-portion to the quantity of matter held in solution. I t is also known from the experiments of Dalton and others that from the point of maximum density to about 30' above or below it, * Annales de Chiniie tome Ixx. an. 1839 p. 81 406 Messrs. Pitlyfiiir and Joule on water and dilute solutions expand according to the square of the temperature fiom that of greatest density. From Iles-pretz's table of the expansion of water it appears that the law is not true as far 8s 212'. As far however as it does hold good it is evident from the properties of the parabola that the volume occupied by a salt in solution will increase in arith-metical progression with the temperature at which the experi-ment is made.For instance let a a in the following diagram be a parabola representing the expansion of water and let b b be a similar Let the Ktter parabola have its vertex or point of greatest density opposite 30° while the former parabola has its vertex at PO0; then x x 2 a! z" a? &c. quantities which increase in arith-metical progression will represent the volumes occupied by the salt in solution at the temperature of loo Zoo 30° dtc. arabola representing the expamion of a solution. In a similar manner it may be shown that the volume occu-pied by each equivalent of'a salt in solution at any 6' riven tem-perature will increase with the density of the solution. In order to ascertain the amount of influence exercised by a change in the position of the point of maximum density we have made a series of experiments on the expansion of water and of solutions by heat which we propose to lay before the Society in a succeeding memoir.In order however to render evident the augmentation of volume caused by increased den-sity we have constrwted the following table of the volume Alomic Volume and Specijc Grauuity. 407 occupied by 172 grains or one equivalent of sugar in solu-tions of different degrees of density. TABLE I. . Ratio of the quantity of sugar to the quantity of water in which it was dissolved. 1 120 1 1 l O i 1 1 3 1 Temperature. Volume in pain memms of water. I t So" 52 52 58 99-00 105*09 107.01 108.06 I As the rate of expansion of dilute solutions is so near that of water it was in most cases sufficient for a very close ap-proximation to absolute accuracy to take the observation within a few degrees below 60° the temperature of the gra-duation of our volumenometers.Whether this temperature of graduation is the best to adopt is a point which we shall have to discuss in our future communications; but at present it may be sufficient to state that its convenience was considerable, as being the average temperature of our laboratories. In all cases then in the following experiments unless where it is otherwise stated the temperature of the solution was about GOo which was also of course the temperature of the water before the salt was introdaced. In the case of the sulphates of the magnesian class of metals the temperature chosen was higher than Goo in order to make up for n diminished rate of expansion owing to a greater degree of dilution in the solution.The specific gravity of the salts was determined in an equally simple manner. A saturated solution of the salt about to be experimented upon (made by dissolving 'an excess of the salt by heat and allowing the solution to cool) was placed in the apparatus already described and a weighed portion of the salt was then introduced care being taken that the tempera-ture did not vary during the experiment. As the new por-tion of salt could not dissolve the increase in the stem indi-cated the volume due to the quantity of salt introduced and afforded data for calculating the specific gravity.In many cases oil of turpeiitirie was used instead of the saline solution. It was frequently desirable especially in the case of hydrated salts rendered anhydrous to avoid the use of water and in the case of organic compounds also of turpentine; and to meet such cases we constructed the followiiig simple appa-ratus which we believe to possess various advantages. Chem. SOC. Mem. VOL. 11. 2 408 A is the receiver of an air-pump, furnished at the top with a collar and sliding rod. B C is a small graduated tube filled with the substance the v0-lume of which is to be determined; it is closed with a. stopper E perforated with a hole of dimensions so small as to prevent any of the salt from falling out. D is a cup of rriercury placed inirnediately below the graduated tube C.The sketch indicates the position of the apparatus on an air-pump when the experiment is about to be perform-ed. 'l'he receiver is then exhausted as thoroughly as possible and the indi-cation of the siphon-gauge is accu-rately noted. The graduated tube is then lowered by means of the sli-ding rod until it touches the bottom of the cup containing the mercury, which after the admission of air flows into the tube until it is filled. The whole contents of the tube are then throwti into water and the salt is washed away by decantation. The mercury is dried by bibulous paper and restored to the tube. If the temperature be different from that which it possessed in the first part of the experiment it is restored to the origi-nal temperature or a correction is made for the difference.It is now obvious that the space in the tube unoccupied by the mercury is that which was formerly filled with the salt. 'Po this however must be added a slight correction tbr the imperfect nature of the vacuum which is not Torricellian,-a correction which need not exceed of the volunie observed. With th&e preliminary descriptions ant1 observs-tions we now proceed to describe the details of our experi-ments throwing them into various classified groups of salts, for the purpose of easy reference. The first group described is remarkable for containing a large amount of water of hydration. SuZphate of Copper CuO SO + 5HO = 124*88.-The third part of an equivalent of this salt 41W grains dissolved in 3140 grains of water at 3Z3 with an increase of 13.15 but dissolved in water at goo with an iucrease of 15'0.Messrs. Playfair and Joule on Cuo So + 5H0 vol. in solution 45.0. Half an eqiiivalent of this salt 62*44 grains being immersed in a saturated solution occupied the volume of 2'7'7 water-grain measures Atomic Volume and Specifc Gravity. 409 Sp. vol. Sp. gr. CuO SO + 5H0 vol. of salt 55.4 ... 2*254 Kopp fouiid for the specific gravity of this salt the number 2.2 74. SuZphate of AZumina Al 0, 3S0 + 18 HO= 333*7.-The salt used in the experiments was carefully prepared and obtained in tolerably good crystals. The eighth part of an equivalent 41*7 grains dissolved in 1000 of water with an increase of 20-0 in otie experiment and 19.9 in another the temperature of observation being 51'.I. Sulphate of alumina vol. in Eolution 160% 11. ... ... e.. ... 159*2 &lean . . 159*6 The same quantity of salt thrown into turpentine caused in two experiments an increase of 25.0 and in a third of 24.9. Sp. gr. ... ... ... 199.2 ... 1-675 Mean . . 199'6 ... 1*671 I. Sulphate alumina vol. of salt 200*0 ... 1.668 I r. -Sui'phate of Soda NaO SO + loHO = 161*48.-Sulphate of soda crystallized out of' a strong warm solution carries down 10 atoms of water. Of this salt about one-fourth of an equivalent (40'4 grains) on being dissolved in 1000 grains of water caused in two experiments an increase of 23'0 at a tem-perature of 59'; and in n third experiment of 22.8 at the same temperature. I. 11. NaO SO + IOHO vol.in solution = 91.8 IIr. ... ... 0 . . ... 91.2 Mean . . 91.5 The same quantity of the sait being immersed in a satiirated solution occasioned an increase of 27.8; arid on a second ex-periment of 2 7 3 at a temperature of 62'. ^_I Sp. gr. I. NaO SO + IOHO vol. of salt 111.1 ... 1.453 11. ... ... ... 108.7 ... 1.485 Mean . . 109'9 ... 1.469 When sulphate of soda crystallizes from a weak cold solu-tion it carries down a quantity of water corresponding to eleven equivalents. In two experiments the volume in solu-tion of salt procured in this way was 98; but we apprehend that the water i s merely mechanical for reasons which will be seen hereafter as the volume of the salt itself by a nieaii of several experiments came out to 1 i9.5 whereas had this 2 E 410 Messrs.Playfair aid Joule on eleventh atom of water been combined it should have been 121. Biborate of Soda NaO ZBO +- 1oHO = 191*23.-on dissolving 40 grains of this salt in 1000 of water the increase was 19.2 at a temperature of 5'. NaO ZBO + 10H0 vol. in soliltion 91.7. Half an equivalent or 95-61 grains ori being placed in a saturated solution occasioned an increase of 5.95 ; and 47.8 grains caused an increase of 27-5; both experiments being made at a temperature of 5s3. Sp. gr. ... 1072% 11. .a. ..* ..* 110 .*. 1.73'3 Mean . . 110*5 ... 1.730 I. NaO ZBO + loHO vol. of salt 11 1 Chloride qf Strontiwn SP c1 + 6Elo = 133*32.--There are two hydrates of chloride of strontium the one with nine, and the other with six equivalents of water.To determine which of these hydrates was under examination 4*324grammes were heated to redness with a loss of 1.76 gramme = 40'47 per.cent. showing that the hydrate was that with six equiva-lents of water which gives by calculation 40.50 per cent. On dissolving 40 grains of this salt in 1000 of water the increase occasioned at a temperature of 56' was 16-0 ; a se-coiid experiment in which the same quantities were used, gave exactly the same result. I. 11. Sr C1 + 6HO vol. in solution 53.8. The same quantity of salt (40 grains) immersed in a satu-rated solution caused an increase of 20.0 at a temperature of 57"; and on a second experiment of 19.7. 11. * * a ..* * a . Sp. gr. 66.6 ... 2*000 65*6 ... 2'030 Mean . . 66'1 ... 2-015 I. Sr c1 -t 6H0 vol.of salt I_ Chloride of Calcium Ca Cl + 6HO = 109*92.-On dis-solving 55 grains or the half of an equivalent of this salt in 1000 grains of water an increase of 2S.O was obtained at the temperature of' 70°; and in a second experiment 27.6 at 60". 56.0 I I. .*. ... *.a 5552 Mean . . 55-6 The same quantity of salt thrown into turpentine caused an 1. CaC1 + 6H0 vol. in solution increase of 32.7 and 32.8 in two experiments. 1. Ca c1 + 6 H 0 V O ~ . of salt Sp. gr. 65.4 ... 1.682 11. .a. ... 65*6 ... 1.677 Mean . . 65-5 ... 1*68 Atomic Volume aiid Spec$c Gravity. 41 1 Chloride of Mugnesiuin Mg C1 + 6HO = 103*16.-Millon has lately described this salt as containing 6; atoms of water ; but as we have not been successful enough to obtain this hy-drate we retain the old formula.25'54 grains or the fourth of an eqnivalent dissolved it 1000 grains of water at 53O, with ail increase of 14-0. Mg C1 + 6130 vol. in solution = 56.0. r 3 1 he same quarit respectively 16.5 ; c I. Mg CI ,+ 11. ... ity 25-54 grains gave in four experiments, 16-0; 16*4; 16.5. Sp. gr. 6HO volume of salt 66.0 ... 1-548 ... ... ... 64*0 ... 1*595 111. ... 0.. ... ... 65.6 ... 1*557 ... 66*0 ... 1.545 1v. 0 . . .* ... Mean . I 65'1% ... 1.562 -The salts'now examined are not calculated on account of the deliquescent character of several of them to produce absolutely accurate experimental results ; but notwithstanding this circumstance the determination of their volumes is suffi-ciently uniform to indicate the theory.The actual volume observed for each of the salts in soliltion when divided by 9, the atomic volume of water yields as the quotient the same number as that representing the atonis of water in the salt. Hence it is quite certain that the salts now described dissolve in water without adding to its bulk more than is due to the liquefaction of the water in chemical combination with them. The volumes of the salts in their solid state possess a num-ber considerably higher than that representing the liquid vo-lume but affect a divisor which is the same for all the salts, allowing for errors of experiments or for alterations cmsed by incidental circumstances. This divisor is a number e;;her equal or approximating to 11. When the volunies of the salts in the solid state are divided by this number the quotient represents the number of atoms of water attached to the salt.The most natural view of this circumstance is to suppose that water in combination as a solid with R salt possesses a higher volume than liquid water just as in the case of ice. If this view be correct the atomic volume of the salts described is the same in the state ofa solid as when in solution the only difference being that in the one case the volume is expressed by liquid in the other by solid water. In this case however, water in combination with a salt does not possess the same volume as ice which according to our experiments detailed in another part of this paper has a volume of 9.8 and not of a number approaching to 1 1 412 Messre. Playfair and Joule ou Yet there is nothing extravagant in the idea that water combined with a salt may have a volume different from that of ice.Indeed we are inclined to be of the opinion that ice itself represents nearly the mean of the volume of water un-combined and that of combined water. Be this as it may it will be observed as we proceed that the number 1 1 is the best exponent of one class of our experiments on specific gra-vity ; and therefore without resting its claims to acceptance entirely on the present experiments we assume it in the fol-lowing tables as the theoretical result for each class of salts. With these views we tabulate the experiments which have been already detailed. TABLE 11.-Showing the volumes occupied by certain salts containing a large amount of hydrate water.Name. ~~ ~ Sulphate Sulphate Sulphate Biborat e Chloride Chloride Chloride copper . . . .Yt } alumina ..?} soda.. . . . . .!} soda .... yf} strontium0!} calcium ..yf} mag nesiui! } Designation. Formula. Cuo SO3+5~I0 A1#,,3S0,+18HO NaO SO3+ lOHO NaO 2B03+10H0 SrC1+6HO CaCI+ 6H0 MgC1+6HO -I-2 B * Atomic -9 . Weight. 2; 1 c. -124.88 45. 333.7 159.6 161.48 91.6 191.23 91-7 133.33 53.3 109.92 55.6 10216 56.0 I Volume as salt. 5 18 10 10 6 6 6 -55 2.270 2.254 198 1.685 1.671 110 1.468 1.469 110 1.738 1.730 66 2.020 2.015 66 1.665 1.680 66 1.548 1.562 There. are some salts which do not take up any space in solution except that due to their water but which assume a volume due to one of their constituents on becoming solid; the potash and ammonia alums are examples of this class.Szilphate of Alzimina and Potash A1,0,3SO + KO SO, +24HO = 474*95.-59 grains of alum dissolved in 1000 grains of water gave the increase of 27.0 in one experiment and 27-1 in another both at the temperature of 60°. I. Alum volume in solution 21'7.3 218*1 &Jean . . 217.7 - I I. ... .. Atomic volume and Spc@c Gravity. 415 On throwing 59.37 grains into a saturated solution an in-crease of 34.4 was obtained in the first experiment ; of 34 *7 in a second ; of 36.3 in a third ; and of 34'2 in a fourth all at a temperature about 60'. Sp. gr. I. Alum vol. of salt 275.2 ... 1.726 Ir. ... e.. 277-6 ... 1.711 111. ..* ..a 274'4 *..1.730 273.6 ... 1.135 IV. ... ... Mean . . 2'75.2 ... 1*726 -Szdphate of Alumina and Ammonia Al,O? 3S0 .+- NH,?, SO + 24HO = 454-26.-20 grains of this salt dissolved in 4100 grains of water with an increase of 10% at 58'. c Ammoniacal alum vol. in solutioii 227.1 The eighth part of an equivalent 56-78 grains immersed in turpentine caused a rise in the stem of 34.9 in one experi-ment and 35.0 in another the temperature being 60'. Sp. gr. I. Ammonia alum 1701. of salt 279-2 ... 1 627 XI. 0 . . ... ... 280.0 ... 1.623 Mean . . 279-6 ... 1-625 Chrome Alunz Cr203 3SO,+KO SO + 24EJO = 504.1. -On dissolving 32 grains of' this salt in 4100 grains of water, an increase of 13-7 was effected at 37'. Chrome alum vol. in solution 215.8 In two experiments 63 grains of this salt thrown into tur-pentine caused an increase of 34.5.Sp. gr. Chrome alum volume of salt 276 ... 1W6 Iron Ammonia-alum Fe,O, sSO,+NH,O SO + ZsHO =481*03.-on dissolving 30*06 grains in 1000 grains of water an increase of 14-3 was obtained at c? temperature of 37O. Iron alum vol. in solution 228 The eighth part of an equivalent 60*13 grains produced an increase of 35.0 nieasures when thrown into turpentine. Sp. gr. Animoniacal iron alum vol. of salt 280*@ ... 1.718 Pyrophosphate of Soda 2Na0 PO + ~ o H O = 224.15.-The eighth part of an equivalent of the crystallized pyrophos-phate 28 grains dissolved in 1000 grains of water with an iii-crease of 1 1 9 in one experiment and of 11.3 in another the temperature in both cases being 58' 414 Messrs.Playfair and Joule 011 Pyrophosphate of soda vol. in solution 89% ... 0 . ... 90.4 Mean . . 90.0 On immersing 56.04 grains of the salt in a saturated solu-tion an increase of 30.5 was obtained in two experiments. 275.2 079.6 276.0 2WO 122 sp. gr. Pyrophosphate of soda vol. of salt 122.0 ... 1.836 ---25 275 1.7271.726 25 275 1.652 1.625 25 275 1-833 1.826 25 276 1.7491.718 11 121 1.8521°836 By tabulating the results thus obtained we find the follow-ing relationship between the class of alums. TABLE 111.- Showing the volumes of certain Alums*. Ammonia alum. Chrome alum ... Iron alum ... { ?’~$U,”,D,”””} Designation. jvo1-a in solution { A12$r3&%H40 1 454.26 227.1 I 25 { cr2$~~~4$oKo’} 504.1 215.8 24 Fe2?$~34$~H409} 481.03 228 25 2Na0 PO,+lOHO 224.15 90 10 I Potash alum ...I { A1203~3S039K07S03 474.95 217.7 24 +24HO 11 1 1 I -A 9 R P e -216 225 216 225 90 I_ Volume in state of salt.. . The peculiarity of the salts described in the above table is, that the quotient of the divisor for the potash alums in the solid state is not the same as in the state of solution and that the ammoniacal alums possess one volume in solution greater than the corresponding potash alums both of which peculi-arities will find an explanation as we proceed. Pyrophos-phate of soda shares this peculiarity and is therefore intro-duced into the table. W e now proceed to describe a class of hydrated salts, in which the divisor for the solid volume is certainly not the number 11.Carbonate of Soda NaO C0,;t 1oHO = 143*4.-On dis-solving 35-85 grains of this salt in 1000 grains of water the increase was 22.5 in one experiment at 6S0 and 22.9 in a second experiment at 65’. 1. NaO CO -+. 1oH0 vol. in solution 90.0 XI. ... ... ... ... ... 91.6 Mean . . 90-8 ** Vide conclusion for explanation of the high volume of ammonia alums Atomic Volume and Spec+ Gravity. 415 On throwing 35.8 grains of the salt into turpentine the in-crease was 24.7 24'5 24.6 and 24.8 in consecutive experi-ments with different specimens. SP. gr* I. Carbonate of soda vol. of salt 98*8 ... 1.451 II. ... ... ... 98*0 ... 1.463 111. ... ... ... 98*4 ... 1'457 IV. ... ... .*. 99.2 ... 1.446 Mean . . 98% ... 1.454 - -Bhombic Phosphate of Soda 2NaO HO PO + 24HO = 359*1.-'rhe eighth part of ail equivalent of this salt 44.9 grains dissolved in 3000 grains of water with an increase of 27-0 in one experiment and 27'1 in a second; by some mis-take the temperature of the solution has not been recorded.I. Phosphate of soda vol. in solution ~ 1 6 - 0 11. ... ... ... 216-8 Mean . . 216.4 The same quantity. of salt thrown into turpentine caused an increase of' 294 in two experiments and 29.5 in a third. Sp. gr. 2352 ... 1.527 11. ... ... ... ... 235*2 ... 2.527 ... ... ... ... 236'0 ... 1.521 Mean . . 235*6 ... 1-525 I. Phosphate of soda vol. of salt - - 111. Sub-phosphate of soda 3Na0 Po + 24HO = 381-6.-The eighth part of an equivalent of this salt 47.7 grains dis-solved in 1000 grains of water with an increase of 27*1 in two experiments at 48'.I. 11. Sub-phosphate of soda vol. in solution 216-8 The same quantity of salt thrown into turpentine produced an increase of 29.4 in two experiments under favourable circumstances although in another experiment in which we were not satisfied wit11 the state of hydration of the salt the increase was only 28.9. Sub-phosphate of soda 235.2 ..* 1.632 Arseniate of Soda ZNa0 E-IO AsO -+ 24HO = 402%-On dissolving 50.36 grains the eighth part of an equivalent, in 1000 grains of water an increase of' 27.2 was obtained at a temperature of 54'. Arseniate of soda vol. in solution 21'7.6 The same quantity of salt thrown into :L saturaled solution This sait caused an increase of 29'0 in several experiments 416 Messrs.Playfair and Joule on loses its water with such facility that it is almost impossible to obtain it in a state well-fitted for experiment. I n two spe-cimens of salts prepared at different times the volume for the above quantity of salt was 29*7 and 29.8 ; but as in most. cases it was only we give the result most generally obtained. Arseniate of soda vol. of salt 232.0 ... 1'736 Sub-arseniute qf Soda 3 NaO AsO,j- 24HO = 425*2.-The eighth part of an equivalent 53'15 grains of this salt dissolved in 1000 grains of water with an increase of 2'7.0 in one ex-periment and 26'9 in another at a temperature about 55'. I. Sub-arseniate of soda 216'0 ... ... 21 5.2 Mean . 215.6 - 11. The same quantity of salt immersed in turpentine caused I. Sub-arseniate of soda vol.of salt 2 3 5 9 1*808 I I. ... ... ... 236.0 l%01 Mean . . 235*6 1*804 Cune-Sugar C, H, Oil = 171 -60.-25*8 grains of sugar dissolved in 3140 grains of water caused an increase of 14*8 at 39'; 42.9 grains or the fourth of an equivalent gave an increase of 25.0 at 60' in two experiments. I. Cane-sugar vol. in solution an increase of 29.4 and 29.5 in two experiments. 98.4 11. ... ... ... 1 0ODO ... ... ... 100'0 Mean . 99*5 - 111. 300 grains of sugar-candy thrown into alcohol previously saturated with it caused an increase in the first experiment of 18890 in the second of 188.75; in a third experiment, 49.65 grains thrown into turpentine caused an increase of 31.0; and the same quantity in a fourth experiment of 31.1, the temperature in all the cases being about 60'.Sp. gr. I. Cane-sugar vol. of solid 107.5 ... 1.596 I I. ... ... 107.9 ... 1.590 111. ... ... 107.1 ... 1-602 IV. ... ... 107.5 ... 1.596 Mean . . l07*5 ... 1.596 In this section a class of salts presents itself in which the volumes are clearly not represented by any multiple of I I ; yet they are uniforrn in their isoniorphous relations and are seiisibly multiples of the same number. To discover whethe Atomic Volume and S'pecgc Gravity. 417 the solid volume have any relation to that occupied by ice, we have determined the specific gravity of the latter with great care. The distilled water which we converted irito ice was deprived of air by long-continued boiling anti a webhed por-lance being kept at the same temperature during the weighing of the ice.The rise in the stem of the volumenometer in which fragments of ice had previously been placed indicated the volume due to the quantity of ice immersed. On treating in this manner 54.2 grains of ice a rise in the stem of 59.0 was produced; and in R second experiment 52.8 grains of ice oc-casioned a11 increase of 57.5 the temperature in both cases being exactly 32'. I. Ice volume 9.797 ... 0.9186 11. ...... 9.801 ... 0'9183 Mean . . 9*799 ... 0.9184 As the true specific gravity of ice is a subject of much itn-portance we place here all the recorded results as given in Bottger's most useful work on specific gravity and in the first volume of Scoresby's Arctic Regions. tion of the ice was quickly immersed in water at 32 t? the ba-Specific volume.Specific gravity. Specific gravity of ice OW38 Dulk. ... ... 0*937 Irvine. ... ..* 0'945 Williams. ... e.. 0.885 Meineke. 0.. ... 0-905 Heinrich Kraft. ... .me 0.927 Osann. 0 . . ... 0950 Roger and Dumas. ... ... 0*920 Scoresby. Mean . 0'919 The mean of all these experiments differing only i&o from our own determination warrants us in concluding that our result is accurate and that 9.80 may safely be taken as the specific volume of an atom of ice. Now it must at once strike the observer of the previous experiments that this num-ber forms the divisor for the volunies of the sdts described in the present section 418 Messrs. Playfair and J O L I ~ 092 TABLE IV.-Showing the volumes occupied by certain Phosphates, Arseniates Carbonate of Soda and Cane-sugar.Designation, Carbonate of soda NaO CO,+lOHO 143.~ Phosphate of soda { ""-t";4"H"d } 359.' s u d ; - ~ ~ p h ~ ~ } 3Na0 Po5+24HO 381.1 Arseniate of soda { Hy2z6As05} 402*! s ~ ~ - ~ ~ ~ i ~ ~ . m 3Na0 AsO,+24HO 426.: Cane-sugar .... .I C12 H, O, 1 171*( Tolume in solution -E 8 9 R P " 8 -90 216 216 216 21 6 99 -Volume of salt. Connected with the latter group there is a class of salts which come out uniformly with themselves but the divisor of which is not 11 in the solid state. We subjoin them in the fbllowing group. Sulphate of Magnesia MgO SO + 7H0 = 123*86.-When this salt is dissolved in a large quantity of cold water, the volume observed after solution is always less at ordinary temperatures than that due to the water contained in the salt.That this diminution is due to a contraction caused by an af-finity of the salt for water is shown by the fact that anhydrous sulphate of magnesia dissolved in a large quantity of water actually lessens instead of increasing the bulk of the water; and to conipensate for this contraction R certain tempera-ture has to be given to the water. In the following expe-riments with the sulphates of magnesia zinc and iron this circiimstance has been attended to and the temperature is given at which the results come out exact. 31 grains of crystallized sulphste of magnesia were dissolved in 3140 grains of water at 3z0 and caused an increase of 15-22; at 85' the increase was 15-76. MgO SO + 7130 voi. in solution 63. Half an equivalent 61.93 grains being placed in a satu-rated solution of the salt caused an increase of 3 7 ~ 5 in one experiment but in three other experiments the increase was not greater than 37.2 the temperature in all the cases being .54c Atomic Volume and Spec@ Gravity.419 Sp. gr. 11. ... ... ... ... 74.4 ... 1.664 111. ... 0.. ... * e m 74.4 ... 1.664 IV. ... m.. ... ... 74.4 ... 1*664 bfean . . 74.55 ... 1.660 Sulphnte of Zinc ZnO SO + 7H0 = 143*43.-This salt possesses the same property as sulphate of magnesia of causing a contraction when the anhydrous salt is dissolved in n large quantity of cold water. 95.9 grains were dissolved in 3140 grains of water at a temperature of 32O causing a rise in the stem of 14'03. At '30" the rise was 1:*77.ZnO so + 7140 vol. in solution I. MgO SO + THO vol. of salt 75*0 ... 1.651 63. The half of an equivalent of this salt 71.71 grains being thrown into a saturated solution caused an increase of 37'1 ; atid 35-85 grains produced a rise in the stem of 18*6 in two experiments and of 18.5 in a fourth. Sp. gr. 11. ... ... ... *.. 74.4 ... 1.928 111. 0.. ... 0 . . ... 74*4 ... 1.928 IV. ... ..a 0 . . ... 74.0 ... 1.937 I. ZnO So $ 7H0 vol. of s d t 74*2 ... 1*933 -~ ~ Mean . . 74.25 ... 1.951 Sulyhate of Iron FeO SO + 7 H 0 = :38*3.-The fourth part of an equivalent 34.6 grains dissolved in 3140 grains of water at 32' with an increase of 15.25 which became 15-75 at 80'. FeO SO + THO vol. in sollition 63. The same quantity of salt thrown into turpentine gave in one experiment an increase of 18-6 in another of l8*7 and in a third of 18'6.Sp. gr. 11. earn ... 0.. ..a 74*S ... 1*S50 111. S.9 ... 0.. ... 74.4 ... 1,860 Mean . . 74*5 ... 1.857 1. FeO SO + 7H0 1 7 0 1 . of salt 74.4 ... 1.860 SuZphate of Nickel NO SO + 6HO = 131*7&.-This salt we found to contain only 6 atoms of water instead of 7 atoms as usually described; but it is known to crystallize with both proportions. On dissolving 35 grains in 1000 of water the increase obtained was 14.0 at a temperature of 55O. W e have not ourselves obtained the specific gravity of this NiO SO + 6HO = vol. in solution 52-7 420 Messrs. Piayfair and Joule 078 salt but this has been determined by Kopy who gives it at 2.037 without however describing the character of the hy-drate which he examined.It is possible therefore that it niay not be the same as that which we have examined; but presuming it to be so the volunie of this salt according to Kopp would be Sp. gr-NiO SO + 6HO vol. of salt 64.6 ... 2'057. The volumes of the magnesia11 sulphates with 7 atoms of water are obviously less than those which would result were they multiples of the volume 11. But as we have already seen that the water of hydration does not always enter into combination with the volume 11 but occasionally with that of 9.8 or the volume of ice the results obtained may be ex-plained on this view. Graham* in his researches on the phosphates and on the heat of combination drew attention to the fact that the atoms of water seem to be attached to-gether in twos.Millon? more lately has shown that the two last atoms of water in sulphate of magnesia are less firmly attached than the five remaining atoms; that a magnesia11 sulphate in fftct may be viewed as MgO SO + 5HO + 2H0. That 5 atoms of water form the natural numbers for the mag-nesian sulphates we have evidence in the salts of copper and manganese both of which possess these 5 atoms of water in combination with a volume of 11 at least. CuO SO + 5HO vol. of salt MnO SO + 5HO ... 57'6 (Kopp.) 55% (P. and J.) As then the two additional atoms of water are retained by a less feeble affinity than the remaining five niay we not as-sume that they are present as in the case of other salts pos-sessing a feeble affinity for water with the volume of ice, whilst the original 5 atoms possess the higher volume of 11 ? The following table will show that this hypothesis gives re-sults by calculation which do not differ widely from those ob-tained by experiment.* Phil. Trans. part 1. 1837 page 67. + Annales de C'himie 3 sdrie t. xii. p. 134 Atoniic Volume and Spec$c Gravib. 42'1 TABLE v. I tion. Volume of adt. Volume in solu- Designation. --- I 1 I I I 74.55 5+2 74.6 1.660 74-25 5f2 74.6 1.926 74.5 5+2 74.61.854 64.6 5+1 64.82.033 1.660 1-93] 1.857 2037 Before leaving this section we would sum up some of the principal facts observed. In the first place it is of niuch im-port;;ince to know that these salts dissolve in water without increasing its bulk tnore than is due to the water attached to them as crystallized water.The acid and bases entirely dis-:tppear in the water which is attached to them ; arid so closely does this rule prevail that the atom of basic water in the tri-tmic arseniates and phosphates has ceased to play the part of water either in solution or in the solid state. In the condi-tion of solid salts we find four classes to which we have drawn tittention. The first of these is represented by salts having their water firmly attached and possess as a divisor for their atomic volume a number equal or approaching to 11 ; and we have concluded as the quotient of this divisor is alwags the same as the number of atoms of water attached to the salt, that 1 1 is the volume of an atom of water in combination; and hence that the salts have disappeared in this attached water adding to its weight b u t not to its observed bulk.The secontl class of salts in this section is represented by potash alum in which the astonishing result is obtained that the 23 anhydrous atoms of this salt have combined in some way with the 24 atoms of water so as to cease to occupy bulk in solution. The peculiarity of this group is that an additional 11 becomes attached to the solid salt so that the quotient of the divisor is 25 instead of 24. This faact and that connected with the ammoniacal alums in the same group cannot be dis-cussed with propriety in the present place. The third group of salts in this section is one of high in-terest and is represented by salts having their hydrate water attached by a feeble affinity.I n them the volume of th 422 Messrs. Playfair and Joule on water is exactly the same as that of ice itself. Sugar belongs to this category not because the H, O, are feebly attached, for it has yet to be shown that they are present quasi water. The fact however that these 1 1 atonis of hydrogen and oxygen take up the same space as liquid water in solution and as ice in the solid state of sugar and that the 12 atoms of carbon have ceased to occupy space is a matter of supreme interest, and cannot fail to lead to important results when we come to the consideration of organic compounds. The fourth class in this sectioii finds its representatives in the sulphates of the magnesian class of metals and perhaps ought to include the rnagnesian chlorides also.They possess their constitutional water with the usual volume of 1 1 while the water feebly attached is present with the volume of ice. Although then we have four distinct groups in the section of salts possessing a large amount of hydrate water we have only two modifications of volume the one represented by a number equal or approximating to 11 the other by the vo-lume of ice itself viz. 9.8. We now proceed to the consideration of salts which either are destitute of water or contain it in small proportion only. The volumes affected by them must be volumes peculiar to themselves aid not as in the present section to the water with which they are combined. SECTION 11. Sulphates with n s n d l p*oportion of tVater of Hydration, Anhjdrous urtd D021bEe Sulphates.Sulphate of Potash KO SO = 87.25.-HaIf an equi-valent of this salt dissolved in 3140 grains of water of 37', increased 7.2 and at 80° 9.0; the same quantity dissolved in 1000 grains of water at 66' increased 9*0. I. 11. KO SO vol. in solution IS*O A whole equivalent of the salt being placed in its saturated solution effected a rise in the stem of 33*0 at a temperature of 55'; and 8 repetition of the experiment gave the increase 33* 1. Sp. gr. I. KO SO vol. ofsalt 35-0 ... 2.644 33-1 ... 2.636 Mean . . 33*05 2'640 _ I ~ JI. ... ... Sdphate o$ Potash and Subhate of n'ater KO SO I- HO, SO = 136*35.-The fourth of an equivalent (39.08 grains), being dissolved in 1000 grains of water caused an increase o Atomic VoZume and Specij'c Gravity.423 9.0 at 8 temperature of 59O and 33 grains dissoIved in the same quantity of water occasioned a rise of 8.75 at 44O. I. KO SO,+ HO SO, vol. in solution 36.0 11. ... ..* ... ... 36.1 Mean . . 36.05 Half an equivalent (68.2 grains) of the salt previously fused itnmersed in a saturated solution produced a rise in the stem of 27-5; and a second experiment with the same quantity but with salt which had not been fused of 27'6 the temperature on both occasions being 55'. Sp. gr. 55-0 ... 2.479 11. ... ... ... Ci5.2 ... 2.470 1. KO SO + HO SO vol. of salt Mean . . 55*1 ... 2.475 Sulphate of Ammonia NH,O SO + HO = ?5*25.-In three separate experiments in which 7.5.25 grains of' this salt were dissolved in 1000 grains of water the increase was ex-actly 36-0 at 60'.I. 11. 111. NH,O SO HO vol. in solution 36.0 Half an equivalent (37*6 grains) being immersed in a satw rated solution at 49" caused in two experiments an increase of 2 1 05. Sp. gr. I. 11. NH,O SO + HO vol. of salt 43.0 ... 1T50 Sulphate of Ammonia and Sulphate of Water NH 0 SO + HO SO3= 1 i5.35.-Half an equivalent (57.7 grains) of' this salt dissolved in 1000 grains of' water gave a rise in the stem of 23.0 at 56' in two separate experiments. I. 11. NH,O SO + HO SO vol. in solution 46,O The same quantity of salt being placed in its saturated solu-tion caused an increase of 32.5 in one experiment and of 33 o in a second the temperature in both cases being 58'. Sp. gr. I. NN 0 HO %SO, vol. of salt 65*0 ... 1*$75 ... ... ... 66'0 ...1.747 Mean . . 65.5 ... 1.761 - 11. Sulphate of Soda and Sulphate of Water NaO SO -+ 130, SO = 120*64.-The fourth of an equivalent (30.16 grains) dissolved in 1000 grains of water in the first experiment with an increase of 4.6 in the second of 4.7 both at a tempera-ture of 56'. Chem. Soc. Ment. VOL. 11. 2 429 Messrs. Playfair and Joule on I. NaO SO,+ HO S? vol. in solution 18.4 11. ... ... *. 18.8 Mean . . 18% c_c The same quantity of salt thrown into a saturated solution caused in two experiments an increase of 1190 at a tempera-ture of 54'. Sp. gr. I. 11 Bisulphate of soda vol. of salt 44'0 ... 2.742 AmmonincalSulpliate of Capper CuO SO HO + 2NH3 = 123*0.-The fourth of an equivalent (30.8 grains) of this substance in beautiful large indigo-blue crystals dissolved in 1000 grains of water with an increase of 13.3 in one experi-ment and 13.0 in another the temperature being 54 and 50'.53*2 Ir. ... ... ... ... 52.0 Mean . . 52.6 I. CuO S O HO + ZNH, vol. in solution 61.5 grains of this salt placed in the solution from which it had crystallized caused an increase of 3 4 ~ 3 and on a repe-tition of the experiment of 3494 at a temperature of 60'. Sp. gr. 68.6 ... 11793 ... ... ... 68-8 ... 1*788 Mean . . 68*7 ... 1.790 I. CuO SO, HO +- 2NH, vol. of salt - - 11. Subhate of Copper and Subhate ofPotask CuO SO + KO, SO + 6HO = 291 * R I .-The fourth of an equivalerit (55-32 grains) dissolved in 3140 grains of water at 32' increased to 16'3 and at 72' to lS*O. CuO SO,+KO S03+6H0 vol.in solution 72.0 The same quantity of the salt placed in its saturated solu-tion caused an increase of 24.7 in one experiment and of 24.6 in a second the temperature on both occasions being 55'. Sp. gr. 96'8 . 2.239 11. ... .*. ... ... 98.4 . 2.249 Mean . . 98.6 2.244 Sulphate cf Copper and Sui'phate of Ammotiin CuO SO -+ NH,O SO + 6HO = 199%S.-On dissolving 50 grains of this salt in 1000 grains of water an increase was occasioned in the first experiment of 20-2 in the second of 20-3 both at a temperature of 59'. I. CUO SO,+ KO SO,+ 6H0 vol. of s2lt - I _ _ _ I. Sulphnte of copper and ammonia vol. in solution 80'8 11. ... ... ... ... ... 81.2 Mean . . 81.0 On immersing the same qiinntity in a saturated solution a Atomic Volume and Spec@ Gravity.425 increase of 26*4 was obtained in the first experiment and of 26'45 in the second both at a temperature of $go. I. CuO SOB + NH,O SO + 6H0 vol. of salt Sp. gr. 105.6 .. 1.892 ... ... ... ... 105-8 . 1.889 lMean . . 105.7 .. 1.891 - 11. Sdphnte of Zinc andSulpAate of Potash ZnO SO + KO, SO3 + 6HO = 221*86.-The fourth of an equivalent of this salt (55'46 grains) on being dissolved in 1000 grains of water, increased to 18 at a temperature of 60' in two experiments. I. 11. ZnO SOa + KO SO + 6H0 vol. it solution 72. The same quantity immersed in a saturated solution caused an increase also in two experiments of %"7 the temperature being 56'. I. 11. ZnO,SO,+KO S03+6H0 vol. of salt 98.8 ... 2.245 Sulphate of Zinc and Sulphate of Ammonia ZnO SO + NH,O SO + 6HO = 200.-On dissolving 45 grains of this salt in 1000 of water an increase of 18*0 was occasioned in three separate experiments at a temperature of 58'.Sp. gr. I. 11.111. ZnO SO + NH40 SO + 6 H 0 vol. in soIution 80 On adding the fourth of an equivalent (50 grains) to a sa-turated solution an increase of 26'4 was occasioned in the first experiment and of 26'3 in the second both at a temperature of 55'. Sp. gr. I. Sulph. zinc and ammonia vol. of salt 105*6 ... 1.894 I I. ... ... ... e.8 1092 ... 1*901 Mean . . 105'4 ... 1-897 Sulphate of Magnesia and &&hate of Potash MgO SO, + KO SO 4- 6HO = 202*29.-When a quarter of an equi-valent of this salt (50.57 graias) is dissolved in as many as 3140 grains of water the volume at 32' is only 15'45 but is 18 at 80'.- -This gives for the salt in very dilute solution-MgO SO + KO S03+6H0 vol. in solution 63 at 40' ... ... ... ... 'iZ at 80' The same quantity of salt after immersion in a saturated solution*gave in the first experiment an increase of 24.3 and in the second of 24.4 both at a temperature of 57'. Sp. gr. 97.2 . PO81 11. ... ... ... ... 97*6 . 2'071 Mean . . 97'4.2.076 I. Sulph. magnesia and potash vol. of salt Szilphate of Magnesia and Ammonia MgO SO + NH,O, SO + 6HO = 181*12.-The fourth of an equivalent (45*28 2 F 426 Messrs. Playfair artd Joule O Y ~ grains) being dissolved in 1000 grains of water caused an in-crease of 20.0 at 60' ; and a repetition of the experiment at the same temperature gave the increase 2O*1. I. Sulyh.magnesia and ammonia vol. in solution 80.0 11. ... ... 0.. ... 80.4 Mean . . 80'2 The same quantity of salt placed in a saturated solution, gave on two occasions a rise in thestem of 26.3 at a tempera-ture of 60'. Sp. gr. I. 11. Sulph. magnesia and ammonia vol. of salt 105'2 . l"72 1 Subhate of Iron and Potash FeO SO,+ KO 60,+6HO =216*73.-The eighth of an equivalent (27.09 grains) when dissolved in 1000 of water caused an increase of 9 at a tem-perature of 65'. Sulph. iron and potash vol. in solution 72. The same quantity immersed in a saturated solution occa-sioned a rise in the stem in two experiments 12.3 at a tem-perature of 61'. sp. 6'. 1. IT. Sulph. iron and potash vol. of salt 98.4 ... 2.202 Sulphate of Iron and Ammonia FeO SO + NH40 SO + 6HO = 195*55.-on dissolving 33.45 grains of this salt in 1000 of water the increase in the first experiment was 13'9, in the second 14 both at a temperature of 59"; a third expe-riment with 669 grains gave the increase 25 at the same tem-perature.I. Sulph. iron and ammonia 1 7 0 1 . in solution 78.5 11. ... ... ... 81.8 ... ... ... 81.8 Mean . . 80.5 - 111. 48*89 grains of the salt being projected into a saturated so-lution caused in the first experiment an increase of 26.4 in the second of 26*5. SP. 6r* 105*6 ... 1*851 ... ... ... 106*0 ... 1.845 Mean . . 105'8 ... 1.848 I. Sulph. iron and ammonia vol. of salt - - 11. In the last section we gnve the volumes occupied by those salts which did not occupy any space of themselves but merely that due to heir combined water.The divisor for the vo-lumes observed in solution was therefore necessarily 9 or the atomic volume of water itself. But in this section we have experimented upon salts which take up space quite inde Atomic Volume and Spec@ Gravity. 427 pendent of their water of crystallization even when they con-tain water and yet the most interesting result follows that the same divisor 9 continues for the volumes ascertained by ex-periment. The volumes in solution of the salts examined, allowing for errors of observation are therefore always mul-tiples of 9,-the atomic volume of water. The volunies of the solids are like those of the previous section multiples of one and the same number that number being also as in the former case 11 ; but the ammonia salts do not arrange them-selves under this divisor for reasons which will be explained presently.The averages of the experiments on all the salts we thrown into the following table into which is also in-troduced the exact numbers which would have resulted had there been a strict accordance with the law obviously indicated by experiment. TABLE V1.-Showing the volumes of certain Sulphates with a small pro-portion of Water of Hydration Anhydrous and Double Sulphntes. Name. Sulphate of potarh . Bisulphate of potash Sulphate of ammonia Bisulphate of am-monia ............ Bisulphate of soda.. Ammoniacal sul-phate of copper} Sulphate of copper and potash ...... } Sulphate of copper and ammonia.. . } Sulphate of zinc and potash ...... } Sulphate of zinc and ammonia... } Sulphate of mag-nesia and potash} Sulphate of mag-nesia & ammonia} Sulphate of iron and potash ......} Sulphate of iron and ammonia.. . } Sulphate of nickel and potash ...... } Designation. Volume in solution. Formula. KO SO, KO SO,+HU SO, NH40 SOa+IIO NH,O SO,+HO SO, NaO SOa+HO SO, CUO SO,H0+2NH, CUO SO9 + KOSO, CUO SO3 + NHdO, S 0 3 + 6 H 0 } +bHO } +GI40 } +GHO } ZnO SOS+KO SO3 ZUO SO + N H,O ,SO, MgO SOS+K@ SO, MgO SO + NH40, FeO SO,+ KO SO, +6HO \ FeO S O,'+ N I I 0 S O3 NiO SO + KO SO, +GI10 j 81.25 '1 8.0 136.35 36.0: 75.25 36.0 115.35 46.0 120.64 18.6 123.00 52-6 221.31 72.0 199.88 81.0 221.86 72.0 200*00 80*0 202.29 72.0 181.12 80.2 216.73 72-0 195.55 SO.? 218.99 715 2 4 4 5 2 6 8 9 8 9 8 9 8 9 8 -b 8 3 h P 4 $ F -I8 36 36 45 18 54 72 81 72 81 72 61 72 61 72 Volume in state of ralt.33-0 55.1 430 65.5 44.0 68.7 98.6 105.7 98.8 105.4 97.4 105.2 9s.4 105.8 100.0 -6 8 9 p" 8 8 * 5 -33 55 44 66 44 ... 99 99 99 99 99 99 99 99 9 428 Messrs. Playfair and Joule OIJ The correspondence between the observed arid calculated results in the preceding table as far as regards the potash salts is so striking as to remove any doubt of the basis upon which the calculations are made. I t is therefore of interest to consider the results indicated by the table a little more in detail.The first point of remark is that in every case the ammoniacal salt has one volume greater in solution than the corresponding potash salt. Sulphate of potash possesses two volumes in solution ; sulphate of ammonia. divested of one vo-lume for its atom of water possesses three. These volumes are respectively carried through the whole class of double sulphates. The volumes of these double sulphates are made up of the sun) of the volumes of their constituent salts which appear therefore to be united unchanged. W e saw in the previous section that the magnesian sulphates dissolve in water without increasing its bulk more than is due to their water of combination. The same takes place in their double sulphates, for subtracting the volumes of the atoms of water which have been carried by the sulphates into their union with sulphate of potash the remainder shows t,he volumes belonginu to the latter salts as indicated by direct experiment.%his is strikingly exemplified also by bisulphate of soda. Srilphate of soda was shown in the last section to possess no volume in solution and in this acid salt we find that the sulphate of soda has in solution ceased to occupy space for the resulting vo-lume of the acid salt is only 18 or 9 x 2 which is the atomic volume of sulphate of water as ascertained by the volume occupied by it in bisulphate of potash and bisulphate of am-monia and as determined also by a calculation which we have made of the volume occupied by hydrated sulphuric acid in a dilute solution founded upon recorded specific gravities.Although the amnioniacal sulphates on account of their analogy to the potash salts have been introduced into the above table it is obvious that the numbers representing their volumes are too wide from the theoretical numbers to be con-sidered multiples of 11. Hydrated sulphate of ammonia af-fects four volumes 11 x 4 but the anhydrous salt obeys a diflerent law. On immersing in turpentine 33-15 grains of anhydrous NH4Q SO, the increase was 19.6 arid 19.5 the mean being 19-55 water-grain measures. This gives 39- I as the vol. of the equivalent and 9.8 x 4 = 39.2. Anhydrous sulphate of ammonia affects therefore 4 vol. of ice; and the double salts consist of the magnesian sulphates with 6 equiva-lents of water attached to a n equivalent of anhydrous sulphate ofammonia as will be seen from the following table of their solid volumes and specific gravities Atomic Volume and Specgc Gravity.Solid volume by expe-riment. 39.1 105.7 105.4 105.2 105.8 Name. Sulphate of ammonia... ................. Sulphate of copper and ammonia ...... Srilphate of zinc and ammonia ......... Sulphate of magnesia and ammonia. .. Sulphate of iron and ammonia ......... Specific vo2:tby gravity by theory* ri2Z. --39.2 1.695 205.2 1.891 105.2 1.887 105.2 1.721 105.2 1.848 429 Speciflc gravity bY theory. 1.691 1.900 1.901 1.721 1.858 As one of the members of the group of double salts here described takes LI~? no space of itself it became of' importance to ascertain the volume of the salt when deprived of water, aid also the space occupied by the double salt reduced to the same state.In this examination it was quite uiinecessary to obtain the volumes in solution because it was obvious that salts not occupying in solution a greater volume than that due to their water of hydration would in their anhydrous condi-tion take up no space at all. I n fact we had ascertained that riot only was there no increase in dissolving such salts in water but that actually there was a contraction if the water were in large proportion to the salt; when thisis not the case, the increased expansibility of the solution prevents the con-traction being observed. In the following examination will be found almost all the salts previously described in their hydrated condition with the exception of the phosphates and arseniates which we re-serve for another paper.Sziclphate of Magnesia MgO SO,= 60*86.-Half an equi-valent of this salt 30'43 grains thrown into turpentine, caused an increase of 11.0 ; but in a second experiment the increase was 11'5 the teniperature ill both cases being 6.5'. Sp. gr. &I@ So, vol. of salt 22*0 ... 2.766 ... ... 23.0 ... 9646 Mean . . 22.5 ... 2'706 Szdplzate qf Zinc ZnO SO,= 80*43.-Half an equivalent of this salt 40.22 grains projected into turpehtine caused an increase of 11.05 and in another experiment of 10%. sp. gr. ... .*. 21.6 ... 3'723 Mean . . 21'85 ... 3.681 ZnO SO vol. of salt 2P.1 ... 3.639 Sdphate of Copper CuO SO,= 79*8S.-Half an equiva-lent 39-94! grains of the salt placed in turpentine caused in several successive experiments an increase of exactly 11*0 430 Messrs.Playfair aiid Joule on Sp. gr. cuo so vol. ofsalt 22*0 ... 3%31 Subhate ofIron FeO SO,= 75*3.-Half an equivaleiit of this salt 37.65 grains caused in two experiments with the same salt a rise of 12.0 which gives for the equivalent 24.0 and IL specific gravity of 3.138. Sulphate of CobaZt,CoO,SO,= 77*69.-on immersing 1 9'42 grains of this salt in turpentine an increase of 5.5 was ob-tained in two experiments; this gives for the equivalent 22.0, and for the specific gravity 3*531. SuZphnte OJ'Soda NaO SO,= 71 *43.-On throwing a whole equivalent of this salt into turpentine the increase was only 27.5 in several successive experiments which gives for the specific gravity 2.597.Karsten found its specific gravity to be 2'631 a result approximating to our own; attention is drawn to this circumstance because both results are anoma-lous. SuZphate of Silver Ago SO,= 156*48.-On immersing in turpentine 78*24 grains of this salt the increase was 14*7, which gives as the volume of the equivalent 29'4 and a specific gravity of 5'322. Chromate of Silver Ago CrO,= 168*49.-'rhe fourth of an equivalent of this salt 42-12 grains gave an increase when thrown into turpentine of 7.3 in two successire experiments. This gives 29.2 for the volume of the equivalent and 5.770 for the specific gravity of the salt. SulpAale of Copper and Potash CuO SO + KO SO, = 167*31.-41*82 grains the fourth of an equivalent thrown into turpentine caused an increase of 14.9 in one experiment and of 15.0 in another the temperature in both cases being sp.g''. 54O. CuO SO,+ KO SO, vol. ofsnlt 59% ... 2.807 ... 60*0 ... 2-788 Mean . . 59-8 ... 2T97 - ... .a. SuZpliate of Nickel arid Potash NiO SO + KO SO = 164*99.-41*54 grains caused an increase of 14.2 in one ex-periment and 14.5 in a second the temperature in both cases being 54O. sy. gr. NiO SO,+ KO SO, vol. of salt 56'4 ... 2.925 ... 57.5 ... 28.69 Mean . . 56-95 ... 2.897 - m . 8 ... Sulphate of X i m and PotccsA ZnO SO + KO SO = 167-8G.-41-96 grains the fourth of an equivalent,.placed in tiirpentine caused iln increase of 14*9 in two experiments Atomic Voliime and Spectit;. Gravity. 43 1 sp. gr. 5gm6 ...22316 ZnO SO + KO SO, vol. of salt Sulphate of Magnesia and Potash MgO SO + KO SO, = 148*29.-37*07 grains or the fourth of an equivalent, caused in one experiment an increase of 13.9 and in a second of 13.8 the temperature being 55'. Sp. gr. ... ... ... 55.2 ... 2*686 Mean . . 55.4 ... 2.6'76 Sulphate of Manganese and Potash MnO SO,+ KO SO, = 163*07.-40*8 grains of this salt one-fourth of 2111 equiva-lent placed in turpentine caused an increase of 13.5 in one experiment and 13% in another at a temperatiire of 55'. Sp. pr. ... ... ... 54'4 2.996 Mean . . 549 ... 3'008 SuZphnte ?$'Copper and Amrno?2ia CuO SO,+ NH,O SO, = 145*88.-36*53 grains of this salt thrown into turpentine, caused an increa5e of 16.7 in one experiment and 16.6 in an-other at a temperature of 60'.MgO SO,+ KO SO, vol. of salt 55'6 ... 2.667 -MnO SO,+ KO SO vol. of salt 54.0 ... 3*O20 - ... Sp. gr. 11. ... ... 0.. 6652 ... 2904 Mean . . 66*4 ... 2.197 I. Sulphnte of copper and ammonia 66.6 ... 2.190 Subhate of Zinc and Ammonia ZnO SO + NH,O SO, = 146*0.-30 grains of this salt thrown into turpentine caused an increase of 13.5 at 60". SP. gr. 65-7 ... 2.222 Sulphate of 1Clqnesia and ,4mtnonia MgO SO + NH,O, SO = 127*12.-'rhe fourth of an equivalent (31.78 grains) placed in turpentine caused an increase of 16*5 in the first experiment and of 16.4 in the second. Sulphate of zinc and ammonia vol. o f salt SP gr. 66.0 ... 1.926 ... ... ... 65'6 ... 1.938 Mean . . 65.8 ... 1.932 I. Sulphate of' magnesia and ammonia - I _ _ I I.SuZ'Aate of Alumiira Al,O,sSO,= 171 *95.-This salt and the anhydrous nlums offer difficulties to the correct estima-tion of their specific gravity on account of their great porosity and liability to carry (town air. 'I'tre best mode of obviating this source of error is to introduce a metallic wire previousl 433 Messrs. Playfair nnd Joule on moistened with turpentine into the volumenometer and employ this to break the numerous air bubbles which arise on im-mersing the salts. The following estimations were taken with great care but from this source of error may possibly be in-accurate. The eighth part of an equivalent (21.49 grains) immersed in turpentine and treated as described above gave results varying from 9.8 to 10.0 the mean result being 9-9.sp. gr. A1,033S0, vol. ofsalt 79.2 ... 2.171 Sulphate of Alumina a d Potash A1,0,3S03 + KO SO, = 259*36.-The eighth part of an equivalent (32.42 grains) of anhydrous alum immersed in turpentine and treated as described in the case of sulphate of alumina gave an increase uf 14.5 and 14*6 in two experiments. Sp. gr. I. ,41um vol of salt 116'0 ... 2.236 11. ... ... 116*8 ... 2*220 Mean . . 116.4 ... 2.228 Ammonia Alum A1,0,3S03 + NH,O SO = 238*2.-The eighth part of an equivalent of this salt (29.77 grains) treated as in the previous cases gave an increase of 14'6 iu two ex-periments. Sp. gr. Ammonia alum vol. of salt 116'8 ... 2.039 Carbonate of Soda NaO CO,= ~ ~ 7 . - - T h e equivalent of this salt thrown into turpentine p v e an increase of exactly 22'0 which makes its specific gravity 2.430.Chloride of Magnesium Mg Cl = 43- 12.-The anhydrous chloride of magnesium used in the experiment was made by saturating equal portions of muriatic acid with magnesia and ammonia mixing together evaporating to dryness and heat-ing to redness. Half an equivalent ("24.06 grains) thrown into turpentine, caused an increase of 1 1.0 in one experiment and of' 11.1 in a second. Sp. gr. 22.0 ... 2'187 22.2 ... 2*167 Mean . . 22.1 ... 2.1'77 I. MgCl vol. of salt - - I I. ... ... Chloride of Calcium CaCl = 55*92.-This salt was ren-dered anhydrous by fusing it in a platinum crucible for some time. 28 grains of the fused salt thrown into turpentine, caused at1 iiicrease of 11.3 at a temperature of'63' Atomic Volume and Spec@ Gruuity.433 SP- gr. CaCl vol. of salt 22.5 ... 2.480 Chloride of Cobalt CoCl = 65*0.-on throwing the fourth of an equivalent (16.25 grains) of anhydrous chloride of cobalt into turpentine an increase of 5.5 was obtained in two experi-ments and of 5.6 in a third trial. Sp. gr. r. CoCI vol. of salt 22.0 ... 2,954 11. ... ... 22.0 ... 2.954 111. ... ... 22*4 ... "2902 Mean . . 22*13 ... 2.937 -c; .d % i: .g ti 60.86' 80.43 79-88 75.3 77.69 71-43 -TABLE V1I.-Showing the volume occupied by certain Hy-drated Salts rendered Anhydrous. sc $ 5 %.El i% j g 22.5 21.8 22.0 24.0 22-0 27-5 *t? g.6 4 oa, 3 g.2 $ & & B 'dp 5 8 M8 &J$ U P -2766 2.706 3.656 3.681 3.631 3.631 3.423 3.138 3.531 3.531 ...2.597 ... 5.322 ... 5.770 ... 2,171 3.042 2797 2.998 2.897 3.034 2.816 2.694 2,676 2.964 3.008 2192 2.197 2.212 2.222 1.924 1-932 . . . 2.228 2.039 2:i27 2.427 2.955 2.937 2.187 2.177 Sulphate of magnesia Sulphate of zinc . . . . . . Sulphate of copper.. . Sulphate of iron.. .... Sulphate of cobalt . . . Sulphate of soda.. ... . Sulphate of silver . . . Chromate of silver.. . Sulphate of alumina. Name. Formulae. -MgO so, CUO so ZnO SO, FeO SO, COO SO, NaO SO, Ago CrOs A1,0,3SO3 CuO SO,+KO SO3 Ago so3 2.542 NiO SO,+KO SO3 2-485 ZnO SO,+KO SO3 168.49 171.95 167.31 164.99 167.86 148.29 163.07 145.88 146.0 127.0 359.36, 138.2 53.47 65.0 48-19 55.92 MgO SO,+KO SO, 292 79-2 59.8 56.9 59.6 55-4 54.2 66-4 65.7 65.8 116.4 116.8 224 22.1 22.1 22.5 MnO S03+K0 so3 Sulphate of copper and potash ......} Sulphate of nickel and potash ......} Sulphate of zinc and potash ......} Sulphate of mag-nesia and potash} Sulphate of manga-nese and potash.} s ~ ~ ~ ~ ~ ~ ~ ~ p ~ ' } s ~ ~ ~ ~ ~ ~ ~ i ~ . ~ } s ~ ~ ~ ~ o a f m m m a ~ ~ ~ ~ } Potash alum ......... Ammonia alum ...... Carbonate of soda . . . Chloride. of cobalt ... Chloride of magne-sium . . . . . . . . . . . . . . . CuO SO,+NH,O SO, ZnO SO,+NH,O SO, MgO SO,+NH,O SO3 Al 0. SSO,+KO SO, Al,O,,%SO,+KH,O SO, NaO C02 co c1 I Volumes of anhydrous salts. I -3 - 5 $j .& F 4 --a 2 2 2 2 ...... ... ... 5 5 5 5 5 6 6 6 ... ... 2 2 2 2 c 6 W E g g 35 -22 22 22 22 22 ... ... ... ... 55 55 55 55 55 66 66 66 ... 22 22 22 2 434 The preceding table exhibits various points of great interest as regards isomorphism. Hydrogen has for a long time bee11 recognised by chemists as equivalent to a magnesian metal ; and hence the sulphate of a metal of this class should possess the volume of sulphate of water. The volume of bisulphnte of potash is 55.0 by experiment which leaves 22.0 for that of sulphate of water on dediicting the volume of sulphate of potash which is 33'0; and the same result follows when the volume of sulphuric acid is deduced from bisulphate of soda, if we suppose the sulphate of soda to enter that salt with two volumes.Thus we have -Sulphate of water . . = 22 d 11 = 2 Sulphate of a inagnesian oxide= 22 + 11 = 2 We now see that biwlphate of potash (sulphate of water and sulphate of potash) is exactly equivalent to the double sulphates of the rnagnesian class. Bisulphate of potash (HO SO + KO SO,) = 55 Sulphate of magnesia and potash( MgO SO + KO SO,) = 55. It is now comprehensible why bisulphate of soda should have a volume of L E ~ ~ * O in the solid state and only of 18.0 in a state of solution; because sulphate of soda which assumes a volume in the solid state becomes added to the same volume possessed by sulphate of water while in the state of solution the proper volume of sulphate of soda disappears altogether.Bisulphate of ammonia possesses a volume due to a com-bination of sulphate of water and sulphate of ammonia with a volume of 11 x4 and it will be observed that the same result attends the double sulphates of the niagnesian metals wilh sulphate of ammonia. Bisulphate of ammonia (NH,O SO,+ HO SO,) =66 Siilphnteofammoniaand copper(NH,O,SO,+ cuo,so,) =66, The cause of this singular result is in the mutual conver-tibility of the primitive volumes 9.8 and 11. It is very curious to observe the large nuniber of volumes which have disappeared when the salt combines with water. Thus sulphate of alumina in its anhydrous state possesses a bulk equal to 79*2 which has ceased to occupy space in the hydrated salt ; and still more remarkable instances of this are seen in the alums which add to this the volunies of' their alka-line sulphates.A curious result obtained in the examination of the hydrated alums is now explicable. W e found that the potash alums took u p in solution only the space due to their water; but that the space occupied by them in the state of salts was one volume in addition to this quantity. In the pre-Messrs. Playfair mid Joule oa (Vide Section V. Atomic Volume and SiieczJc Grmit'9. 4.95 ceding section we observed that sulphate of potash possessed the singular property of expanding one volume in becomirig solid; 9 x 2 in a state of solution becoming 1 1 x 3 in the state of a salt. I t is impossible to refrain from accepting this as an explanation of the increase of one in the quotient ob-tained by dividing the volumes by their proper numbers 9 and 11-24 Y 9 becoming 25 x 11.The difficulties to which we have already alluded prevent us placing much confidence in our results for the anhydrous alums. Sulphate of alumina seems tu af€ect eight volumes of ice 9-8 x 8 = 78'4; in ammonia alum the latter becomes united to the volume of anhydrous sulphate of ammonia, 9.8 x 8 + 9.8 x 4 = 117.6 ; while potash alum should con-sist of 9% x 8 + 1 1 x 3 = 1 1 1.4. It is unnecessary to re-inark that these theoretical numbers possess only an approx-imation to our experimental results. (Vide remarks on Sec-tion V.) The sulphates of soda and silver and the corresponding chromate are alfio obviously exceptions to the general rule of the solid volume being multiples of 11.Uut in the last section we hat1 similar exceptions in salts whicli ranged themselves under 9 8 or the volume of ice. The sulphates now under consideration have the same divisor if sulphate of soda be not considered an exception as the variation is decidedly too great to be attributed to n mere error of experiment; it ought how-ever to be observed that Mohs gives for the specific gravity of this salt 2-462 a number much more in accordance with theory than our own result ; but as our experiments have been often repeated they niay perhaps be viewed as an aqument in favour of an opinion deduced from other considerations that sulphate of soda has a double atom 27.5 x 2 = 55 which is 11 x 5. Name. Sulphate of soda ...... Sulphate of silver ...... Chromate of silver...... 1% 1 SECTION 111. Nitrates t$c. The nitrates (30 not in general affect a large proportion of water of hydration a i d are therefore well-calculated to sho 436 the volume occupied by anhydrous salts. I t will be observed that they present some peculiarities. Nitrate of Potash KO NO,= 101*3.-The half of an equi-valent of this salt 50*65 grains being dissolved in 1000 grs. of water gave an increase of 18*05 at 45'. Messrs Piayfair and Joule on KO NO, vol. in solution 36.1 The same quantity of Salt 50.65 grains thrown into tur-pentine caused a rise in the stem of 24.5 24.4 24'5 in three successive experiments. Sp. gr. I. KO NO5 vol. ofsalt 49.0 ... 2.067 11. ... ... 48-8 ... 2'075 1x1. ... ... 49-0 ... PO67 Mean . . 48*9 ...2.070 -Nitrate of Ammonia NH,O NO,=SO-fJ.-The volume of nitrate of ammonia in solution was determined by dissolving 40.15 grains of this salt in 1000 grains of water. In one ex-periment the increase in the stem was 22'5 the temperature being 57'; in a second the rise was 23.0 at 63'. I. NH,O NO vol. in solution 45.0 11. ... ... 46.0 Mean . . 45*5 Half an equivalent of this salt well-dried (40.15 grains), on being immersed in turpentine produced an increase in three experiments of 24.7 84.5 24.5. Sp. gr. I. NH,O NO vol. of salt 49.4 ... 1.625 I I. ... ... 49.0 ... 1.639 ... ... . 49-0 ... 1.699 Mean . . 49.1 ... 1'635 - 111. Nitrate of Soda NaO NO,= 85*45.-On dissolving 85-45 grains or one equivalent of this salt in 1000 grains of water, an increase of 27-1 was obtained the temperature being 59' ; but on repetition of the experiment at the same temperature the increase was only 26.0.I. NaO NO, vol. in solution 27'1 I I. ... ... 26.0 Mean . . 26*5 The half of an equivalent of this salt 42.72 grains well-dried qroduced an increase on being thrown into turpentine of 19.6 in three experiments and 19*5 in a fourth trial Atomic Volume und Spec@ Oravity. I NaO NO vol. of salt 39.2 ... 2.180 437 sp. el.. I I. ... ... 39.2 ... 2.180 111. ... ... 392 ... 2*180 ... ... 39.0 ... 2.190 IV. Mean . . 39.1 2.182 -Nitrate of Silver Ago NO = 170~0.-Ou dissolving 4 2 5 grains of this salt in 1000 grains of water an increase of 6.8 was effected at a temperature of 59". Ago NO, vol. in solution 27-2.The same quantity of salt 4.25 grains thrown into turpen-tine produced an increase of 9.8. Sp. gr. Ago No vol. of salt 39.2 ... 4.336 Nitrate of Lead; PbO NO,= 165.75 .-This salt gives very unsatisfactory results on being dissolved in water; at low temperatures the volume for the atom is equal to nearly 18.0, or 9 x 2. But at higher temperatures the volume in solution approaches nearly to 27.0 or 9 x 3; and although the re-sults do not come out exact unless corrected for expansion, we are inclined to view the latter as the true result. 83 grs. dissolved in water gave an increase of 12.5 ; in a second es-periment of 12.7 both at a temperature of 65'. 25*0 ... ... 25-4 Mean . . 25-2 PbO NO, vol. in solution -The fourth part of an equivalent 41.43 grains immersed in turpentine gave an increase of 9.7 ; 82*87 grains gave the in-crease 199 ; and in a third experiment 19.0.sp. gr. I. PbO NO, vol. of salt 389 ... 4.273 IT. ... ... 38*4 ... 4*316 ... ... 38-0 ... 4.362 Mean . . 38-4 ... 4.316 - 111. Nitrate of Barytes RaO NO,= 130'85.-Half an equiva-lent of this salt 65*42 grains dissolved in 1000 grains of water with an increase of 13.5 at a temperature of GOo; and a repetition of the experiment was attended with the same result. BaO NO, vol. in solution 27.0. The same quantity of salt immersed in turpentine caused an increase of 19'8 in three experiments and 20-0 and 20.2 in two other experiments; the salts being all different speci-mens and decrepitated previously to the experiment 438 Messrs.Playfair ancl Joule on Sp. grw I. BaO NO, vol. of salt 39-6 ... 3.304 11. ... ... 39.6 ... 5.304 111. ... ... 39*6 ... 3.304 IV. ... 40.0 3*271 ... ... 40-4 ... 3.238 Mean . . 39.84 ... 3.284 ... ... - V. Nitrate of Strontia = 106.O.-HaIf an equivalent of this salt 53 grains was dissolved in 1000 grains of water with an increase of 13.0 the temperature being 62'; 106 grains dis-solved in 1000 grains of water with an increase of 27-0 at a temperature of 63'. I. SrO No, vol. in solution 26*0 ... ... ... 27.0 Mean . . 26*5 _-__ 11. 53 grains immersed in turpentine gave an increase of 19.6; and this result was confirmed by a second experiment. S]'. gr. SrO NO, vol. of salt 39.2 ... 2'704 Nitrate of Black Oxide of Mercury Hg,O NO + 2HO = 282*0.-This salt in beautiful large transparent crystals, was dissolved in water containing nitric acid to prevent the formation of a subsalt; 7 0 5 grains thus treated caused an in-crease of 13.5.Protonitrate of mercury vol. in solution increase in three experiments was 14'8 14'7 and 14.7. 54.0 On immersing the same quantity of salt in turpentine the Sp. gr. I. Protonitrate of mercury vol. of salt 599 ... 4*763 11. ... ... ... 58*S ... 4-796 111. ... ... ... 58-8 ... 4*196 Mean . . 58.9 ... 4.785 Nitrate of Copper CuO NO + 3HO = 120*8.-Half an equivalent (60-4 grains) dissolved in 1000 grains of water with an increase of 22*4 at SO0 ancl in a second experiment of 22*6; in a third experiment 3 0 9 grains dissolved in the same quantity of water gave an increase of 11*4.44.8 11. ... ... 45*2 ... ... 45.6 Mean . . 4 5 9 I. CuO NO, vol. in solution - 111. In two experiments 60.4 grains thrown into turpentin Atomic Volume and Specific Gravity. 439 caused an increase of 295 which gives for an equivalent of the salt the volume 59.0 and a specific gravity 2*047. Nitrate f13 Magnesia MgO NO + 6HO = 128*8.-The fourth part of an equivalent of crystallized nitrate of magnesia (32.2 grains) dissolved in 1000 grains of water at GOo with an increase of 18- 1 and 18.3 in two experiments. I. MgO NO + 6H0 vol. in solution 73.2 11. ... *.* ... 72.4 Mean . . 72.8 The same quantity thrown into turpentine produced an increase of 22.0 which gives for the volume of an equivalent of the salt 88’0 and for its specific gravity 1*464.Nitrate of Bismuth BiO NO + 3HO = 160-33.This salt being decomposed when thrown into water is not fitted for determining volume by solution; but when 80.16 grains were thrown into turpentine the increase was obtained in two experiments of 29.2 and of 29-4. Sp. gr. I. BiQ NO + 3HO vol. of salt 58*4 ... 2.745 58% ... 2.727 Mean . . 58*6 ... 2.736 - _- 11. ... ... ... Basic Nitrate of Mercury 2Hg0 NO + 2HO = 2919. -This salt cannot be dissolved in water without the forma-tion of a subsalt unless the water is used in small propor-tion; it is therefore unfitted for our experiments as far as regards the volume in soluthn. On immersing 68.7 grains in turpentine an increase of 16.2 was obtained in two suc-cessive experiments. ‘Fhis gives 68% as the volume of the equivalent and a specific gravity of 4-242.Basic Nitrate of Lead ZPbO NO = 277*72.-This salt is so insoluble that it is difficult to determine its volume in so-lution with any great degree of accuracy. The sixteenth part of an equivalent dissolved in 1004) grains of water gave an increase of 2-6 which seems to indicate a volume of 9 x 5. 6943 grains being immersed in turpentine gave an in-crease of 12.3 in several experiments. Sp. gr. Basic nitrate of lead vol. of salt 49-2 ... 5-645 The same multiple relation of 9 is carried through all the salts of this class dissolved in water. The divisor for the solid volume is however different from the salts of the pre-vious sections. Exceptional cases were pointed out in their examination in which 9.8 or the volume of ice became the divisor ; and in the present group of salts we observe a won-derful uniformity in this respect.Chcm. Xoc. Mem. VOL. rI. 2 440 Messrs. Playfair and Joule on TABLE VII1.-Showing the volumes occupied by certain Nitrates. - -101.3 '36.1 80-3 145.5 85.45 26.5 170.0 127.2 165.75 25.4 130-85 27.0 106.0 26.5 282.0 54.0 291.0 ...... 277.79 ...... 160.33. . . . . . . 120.8 45.2 128.8 172.8 Designation. I -4 5 3 3 3 3 3 6 5 8 Name. Nitrate of potash ... Nitrate of ammonia Nitrate of soda ...... Nitrate of silver .\.. Nitrate of lead ...... Nitrate of barytes .. Nitrate of strontia .. Nitrate of black oxide of mercnr y } I KO NO, NaO NO, I'bO NO5 NII,O NO, Ago NO5 BaO NO, SrO NO, Hg,O N05+2H0 Nitrate of bismuth.Nitrate of copper... Nitrate of magnesia Volume in solution. RiO N05+3€10 CuO N0,+3IIO MgO N0,+6HO -h Q . ;E 22 0- > -36 45 27 27 27 27 27 54 ... ... ... 45 72 -Tolume in state of salt. --.__ 49-0 2.067 2.070 49.0 1.639 1.635 39-2 2.180 2.182 39.2 4-336l4-336 39.2 4.228 4.31 6 39.2 3.338 3.284 39.2 2.704 2.704 58.8 4.796 4.785 68.6 4.242 4.242 49.0 5.667 5.645 58.8 2.727 2,736 58.8 2-054 2.047 88.2 1.460 1.464 It is almost superfluous to offer any remarks upon this group of salts especially as we shall have to consider several of them in a future section. It cannot escape attention that the nitrates of soda silver lead strontia and barytes possess the same atomic volume as might have been expected from the isomorphism of several of them.Nitrates of soda and potash do not possess the same atoniic volume and therefore their alleged isomorphism deduced from the observation by Frankenheim* of microscopic crystals of nitrate of potash similar to those of nitrate of soda is highly questionable. The principal exception to the volumes of the nitrates now de-scribed being multiples of ice is that of nitrate of lead which has a volume of 38.4 instead of 39.2; but this must be due to the nature of the salt which comes out as unsatisfactorily in a state of solution as in the solid state. SECTION IV. Chlorides Bromides and Iodides. Chloride of Potassium. KCl = 74*7.-On dissolving 37*5 grains of this salt in 1000 grains of' water the increase was 13'3 at a temperature of' 57"; a second experiment with the * Poggendorff's Am.Band xl. S. 447 Atomic Volume and Spec@ Gravity. 441 same quantity gave the increase 13.5 at 5 8 ' ; and a third ex-periment gave 13*7 at 65'. I. KC1 vol. in solution 26*5 11. a*. ... 26*8 Mean . . 26% 111. ... ... 272 The whole of an equivalent thrown into turpentine (the salt having been decrepitated) increased 39.6 and 39.3 in two experiments. Half an equivalent 37.35 grains caused a rise in the stem of 19*6 in two experiments. Sp. gr. I. KCI; vol. of salt 39-6 ... 1*S8? 11. ... ... 39*3 ... 1*900 111. ... ... 3 9 2 ... 1.905 ... ... 39.2 ... 1.905 IV. Mean . . 39.3 ... 2*900 -Chloride of Ammonium NH C1= 53*66.-Half an equiva-lent 26-83 gains dissolved in 1000 grains of water with an increase of 17.5 at a temperature of 60'; in two other expe-riments at 63' the increase was 18*0.I. NH Cl vol. in solution 35.0 11. ... ... 36*0 1x1. ... ... 3 6-0 Mean . . 35*7 Our experiments on the specific gravity of this salt gave 1*578 as an uniform result indicating a volume of 34.0. Bromide of Potassium KBr = 117*6.-The fourth part of an equivalent 29.4 grains on being dissolved in water at 49', gave in two experiments an increase of 7.2; which gives for the volume of the salt in solution 28%. The same quantity of salt immersed in turpentine at 63O caused an increase of 11-0 in two experiments. Sp. gr. KBr vol. of salt 44.0 ... 2*672 Iodide of Potassium KI = 165*82.-This salt was decre-pitated and on dissolving 41-5 grains gave an increase of 11*0 at 57' ; a second experiment with 83 grains gave an in-crease of 22.0 at 55'.I. KI vol. in solution 44 ... ... 44 Mean . . 44 - 11. On projecting 41-45 grains of this salt previously decrepi-tated into turpentine an increase of 13*6 and 13.5 was pro-duced in two successive experiments. 2 G 44 2 Messrs. Playfair and Joule on Sp. gr. I. KI vol. of salt 54.4 ... 3.048 IT. ... 54.0 3.070 Mean . . 54-9 ... 3.059 ... ... Chloride of Sodium NaCl= 58-78.-The whole of an equi-valent of this salt previously decrepitated dissolved in 1000 grains of water at SO" with a rise of 18.0; and in a second experiment of 18.2 ; in a third experiment 11 8 grains of salt were dissolved in 1000 grains of water at 62' with an increase of 38*0.I. NaCl vol. in solution lS*0 11. ..* ... 18-2 111. ... ... 18.9 Mean . . 18.3 80 grains of salt were treated as described (page 405) in the mercurial volumenometer and the empty part of the tube, after the restoration of the mercury showed a volume of 40.0. The same quantity thrown into alcohol previously saturated with it gave an increase of 39.5. The whole of an equivalent, 58*78 grains thrown into a saturated solution caused an in-crease of 29.3. Sp. gr. 1. NaC1 vol. of salt 29.4 ... 2,000 11. ... L.. 29-0 ... 2.026 1x1. ,.. ... 29.3 ... 2.006 Mean . . 29-23 ... 2-011 Bromide of Sodium,NaBr + 3HO = 128*70.-On dissolving 25*7 grains of this salt in water an increaze of 9-3 was occa-sioned in two experiments at a temperature of 5 3 O .I. 11. Na Br + SHO vol. in solution 46 The same quantity of salt put into turpentine caused an increase of 11. Na Br + 3H0 vol. of salt 5 5 ... 2.340 Chloride of Barium Ra c1 $- 2 H 0 = 122*S3.-30*7 grains dissolved in 1000 grains of water increased 7.0 at a tempera-ture of 58O; a second experiment in which 20 grains of the salt were dissolved gave an increase of 4.5. I. Ba C1 + ZKO vol. in solution 28*0 I I ... ... 2 7-6 Mean . . 27.8 The fourth of an equivalent 30.7 grains being immersed in a saturated solution gave an increase of 9*7 at a tempera-ture of SO"; and the same quantity in two other experiments gave an increase of 9% Atomic Volume and Specgc Gravity. 443 Sp. gr. I. Ba C1 + 2HO vol.of salt 38.8 ... 3.166 11. ... ... 39.2 ... 3*133 111. ... ... 39.2 ... 3013.3 Mean . . 39-07 ... 3.144 Perchloride of Mercury Hg C1= 136*9.-The fourth of an equivalent 34.2 grains of corrosive sublimate on being dissolved in 1000 grains of water gave an increase of 4.6 at a temperature of 62"; a second experiment with the same quantity was attended with the same result. I. 11. HgC1 vol. in solution 15-4 Half an equivalent (68'45 grains) thrown into a saturated solution of the salt caused an increase of 11*0 at a ternpera-ture of 56'. Sp. gr. I. Mg c1. vol. of salt 92 ... 6923 C'lZoride of Hydrogen HCl = 36*47.-It was of interest to ascertain the volume of hydrochloric acid in order to corn-pare it with the other chlorides of the magnesian metals when dissolved in water.It was natural to expect that the volume of muriatic acid in dilute solutions would be different from that possessed by it in its concentrated state; and therefore the following experiments must be viewed in this light. Beligot's salt the bichromate of the chloride of potassium on dissol-ving. in water was decomposed into bichromate of potash and munatic acid and the volume of the latter mas obtained by deducting that due to the former salt and adding the volume of water. The fourth part of' an equivalent of this salt 44*75 grains dissolved in 1000 grains of water with an increase of 13*5 at 65'; and of 13.6 in another experiment at 68'. This result gives for the hole volume of the salt when dissolved 54-0 and 54*4 from which must be deducted 45*0 for the vo-lume of bichromate of potash and 9 must be added on ac-count of the equivalent of water.1. Muriatic acid in dilute solutions 18.0 11. ... ... ... 18.4 Mean . . 18.2 Chloride of Ccpper Cu C1 + 2HO = 85*18.-Half an equi-valent 42.6 grains was dissolved in 1000 grains of water with an increase of 13*4 at a temperature of 60'; on a second ex-periment 47 grains occasioned an increase of 14*0 at a tem-perature of 58'. I. CuCl + 2H0 vol in solution 26.8 11. I.. ... 25.4 Mean . . 26.1 444 Messrs. Playfair and Joule on Half an equivalent 42.6 grains being immersed in a satu-rated solution at 62" caused an increase of 17.0 ; a second expe-riment with the same quantity of salt gave an increase of 16%. I. CuCl + 2H0 vol.of salt 33.2 ... 2.566 11. ..a ... 34.0 ... 2*505 Mean . . 333.6 ... 2.535 Sp. gr. -Chloride of Copper and Ammonium CuCl+ NH,CI + 2HO = 138*84.-34*7 grains of this salt being- dissolved in 1000 grains of water gave an increase of 155 in the first experi-ment and of 15*4 in the second both at a temperature of 68'. I. CuCl +NH4C1 + 2H0 vol. in solution 62*0 ... ... ... 6 1.6 Mean . . 61% - 11. 32*46 grains thrown into a saturated solution caused an increase of 16.1 in two experiments at a temperature of COO, and a repetition of the experiment confirmed this result. Chloride of copper and ammonium vol. of salt 68.8 ... 2.018 Chloride of Copper and Potassium CuCl + KC1 + 2H0 = 159*88.-34*7 grains of this salt being dissolved in 1000 grains of water caused an increase of 11.5 at 6 2 O .CuCl + KCl + 2H0 vol. in solution 53'0 The same quantity (34.7 grains) thrown into a saturated solution caused an increase of 14*3. CuCl + KCl + 2H0 vol of salt 65.9 ... 2'426 Chloride of Tin SnCl + 3H0 = 121*39.-One-fourth of an equivalent (30*35 grains) was dissolved in 1000 grains of water acidulated with muriatic acid with an increase of 9*0 at a temperature of 60'; a second experiment with the same quantity of salt and at the same temperature gave an increase of 9% I. SnCl + 3H0 vol. in solution 36.0 11. ... ... ... 36.8 Mean . . 36.4 The same quantity 3@35 grains of the salt being immersed in a saturated solution yielded an increase of 1 l*O the tempe-rature being 60"; and exactly the same result attended the repetition of the experiment.Sp. gr. SnCl + 3H0 vol. of salt 44.0 ... 2.759 Chloride of Tin and Ammonium SnCl + NH4C1 + 3HO = 175*05.-On dissolving 44 grains of this salt in 1000 grains of water the increase was 18.5 at a temperature of 60"; Atomic Volume and Specgc Gravity. 445 second experiment with the same quantity and at the same temperature gave an increase of 185. I. Chloride of tin and ammonium vol. in solution 72.7 ... ... ... ... 73-5 Mean . 73.1 - 11. On immersing 43-76 grains of the salt in a saturated solu-tion an increase of 20.8 was obtained at a temperature of G O O which gives 83.2 as the volume of the equivalent and 2*104 as the specific gravity of the salt. Chloride of Tin and Potassium SnCl+ KCl + 3HO = 196.09. -On dissolving 24-3 grains of the salt in 1000 grains of water, an increasecof 8-0 was obtained at a temperature of 60'; and 48.5 grains dissolved in the same quantity of water gave an increase of 15.5.I. Chloride of tin and potassium vol. in solution 64.5 11. ... ... ... ... 62.7 Mean . . 63*6 On throwing the fourth part of an equivalent 49 grains, into a saturated solution an increase of 19.5 was obtained a t a temperature of 54". Sp. gr. 78.0 ... 8514 SnCl+KCi+3HO vol. of salt A. Chloride of Mercury and Ammonium HgCl + NH,C1 + HO = 199*8.-On dissolving 49-95 grains of this salt in 1000 grains of water an increase was obtained of 16*0 and in a second experiment of 16*2 the temperature being about GOo in both cases. I. A. Chloride of mercury and ammonium vol.in sol. 64*0 Ir. ... ... ... e.. ... 64.8 Mean . . 64*4 The same quantity of salt thrown into a saturated solution at 60° occasioned an increase of 17.0 in two experiments, which makes the volume of the equivalent 68'0 and the spe-cific gravity 2.938. B. Chloride of Mercury and Ammonium NH,Cl + ZHgCl + HO = 336*4.-On dissolving 42 grains of this salt in 1000 grains of water an increase of 1 o* 1 was occasioned in two ex-periments at 54' and of 10.2 in a third experiment at 60'. -I. 11. NH C1 + 2I-IgCl + HO vol. in solution 8O*Y ... ... ... 81.6 Mean . . 81*2 - 11:. 42 grains or one-eighth of an equivalent thrown into a saturated solution of the salt caused a rise in the stem of 11 in two experiments 446 Messrs. Playfair alzd Joule on Sp. gr. I.11. B. Chloride of mercury and-}88.0 ... 3%22. Chloride of Mercury and Potassiunz KC1 + 2HgC1+ 2130 = 366*5.-The eighth part of an equivalent 45*8 grains, being dissolved in 1000 grains of water caused in tv7o expe-riments an increase of 10*1 at a temperature of 53’. I. 11. Chloride of mercury and p o t a s ~ i u m ] ~ ~ . ~ . The game quantity of salt 45*S grains tbrown into n satu-rated solution caused an increase of 1200 in one experiment and of 12.4 in two other trials the temperature in all the cases being 58’. Sp. gr. ammonium vol. of salt . vol. in solution. . . . . 117.6 53.66 165.fi2 128.70 136.9 3647 85.18 121.39 368.5 - - I. Chloride of mercury and potassium,)96,0 ., 3.81t3 1701. of salt . . . . . . -I- -1-28.8’ 3 27 44.0’ 4 35.7 4 36 34.0 3 44-01 5 45 5121 5 46.0 5 45 55.0 5 18.4 2 1s 22.0 2 18.2 2 18 ........26.1 3 27 33.6 3 36-4 4 36 44.0 4 99.2 11 99 1224 11 2 ... 11. ... ... 99.2 3.694 ... ... 99.2 ... 3.694 Mean . . 98.1 ... 3.735 - 111. Chloride of Mercury and Sodium NaCl + 2HgCl + 4HO =36Sq5.-On dissolving 46-06 grains of this salt in l000grains of water the increase was 12’4 at 63’. This gives for the equivalent a volume of 99.2 or 11 equivalents. The same quantity of salt thrown into turpentine produced an increase of 15.3 which gives for the equivalent 122-4 and for the spe-cific gravity 3*011. A careful consideration of the previous experiments shows that there are two distinct classes of chlorides &c. The first of these is placed in Table IX.and possesses 11 as the divi-sor of the solid. TABLE IX. I 44 33 55 55 22 33 44 121 Designation. --2.672 2.672 1.626 1.575 3.015 3,059 2.340 2.340 6.293 6.223 ............... 2.581 2.534 2759 2.759 3.045 3,011 Name. Bromide of potassium . Chloride of ammonium. Bromide of sodium ... Iodide of potassium ... Chloride of mercury ... Chloride of hydrogen.. . Chloride of copper..... . Chloride of tin ......... Chloride of mercury and sodium ......... Formula. I< Er NH C1 K I NaBr+3HO H C1 Cu C1+2HO Sn C1+31IO 2Hg C1+ Na C1 f4110 } ITg C1 I 1 vol. in solution. Volume of solid. Atomic Volume and Spec@ Gravity. 447 In the second clnss (Table ~ X . A . ) the primitive volume is 9 8 or as in the case of the double chlorides of tin the me-tallic salt enters into combination with the volume 11 ; while NH,Cl remains a multiple of 9%.It is interesting to ob-serve that NH,Cl affects in combination as a solid the same number of volumes which it has as a liquid. 0 h 3 5 -39.2 29.4 39.2 68.6 68.6 83.2 78.4 68.6 88.2 98.0 TABLE IX.A.-showing the Volumes in solution and in the solid state of certain Chlorides. $ 5 .-$ E 25 k!2 MZ ? * -1.90E 2-00( 3.13: 2.331 2.024 2.104 2.501 2.91: 3.814 3.73s Designatioi. I 74.7 58-78 122.83 159.88 138.84 175.05 196.09 199.8 336.4 366.5 Name. --26.8 3 18.3 2 27.8 3 53.0 6 61.8 7 73.1 8 63.6 7 64.4 7 81.2 9 80.8 9 Formula. ' ......Na C1 Chloride of 1)arium ... Ba C1+2HO Chloride of potassium . Chloride of sodium CU Cl+KC1+2HO Cu C1+ NH C1 Sn C1+ NI1 C1 Sn Cl+KCl+SHO I- HE; C1+ NH4 C1 2Bg CI+NH4 C1 +HO 2Hg C1+ KC1 Chloride of copper Chloride of copper Chloride .of tin and Chlolide of tin and A. Chloride of mer-B. Chloride of mer-Chloride of mercury and potassium ...... } and ammonium . . } ammonium ......... } potassium ......... } cury and ainmonium } cury andammoniiim ) and potassium ...... } I vol. in solution. ~ 6 % c, h P - $ B -27 18 27 54 63 72 63 63 81 81 __ 39.3 29.2 39.0; 65.9 68.8 83.2 78.0 68 88 98.1 Volume of salt. The results of the experiments detailed in this section afford strong proofs of the law of multiple proportions and exhibit at the same time that remarkable alteration of the divisor of the solid volumes which we have already noticed so frequently.Thus while many of' the chlorides and bromides are multi-ples of 11 we have decided exceptions in chlorides of potas-sium and sodium which possess for their divisor the volume of ice viz. 9.8; and this reappears in the double salts. It is impossible however not to see that these results are somewhat siiigular for in the double salts the chloride of potassium forces the double salt with 11-hich it is associated to assume the multiples of 9.8 and then exhibits its natural isomorphous relation to chloride of ammonium which per se it did not possess. Chloride of ammonium anomalous in beiiig a multiple of 11 in the solid state assumes f'our volumes, -2; '$ 0 g.! o w G k k h r/iP .5 5 -1.900 2-01 1 3.144 2426 2.018 2.104 2.5 14 2.938 3.822 3.736 448 Messrs Playfair and Joule on multiples of 9.8 in the double chlorides and then presents the same number for its solid volume as chloride of pot,assium.The isomorphism of potassium and sodium is so entirely hy-pothetical that it will not excite surprise to find the volumes of thc chlorides so different. We were less prepared to detect the difference between iodide and chloride of potassium ; but have confirmed it by an examination of iodide of ammonium, 50 grains of which dissolved in 1000 of water with an increase of 18-7 which gives = six volumes for the equivalent a result confirmatory of our determination of five volumes for iodide of potassium; the increase of one volume being in conformity with the usual behaviour of ammoniacal salts.W e shall return $0 the consideration of the chlorides in a fu-ture section. 9 SECTION V . Chromat es. The chromates present a class of salts which offer some peculiarities with regard to their volumes in elucidating which we had occasion to repeat our experiments very often and, therefore give the mean of the results instead of taking up unnecessary space in the Transactions of the Society by de-scribing each experiment individually. Chromic Acid CrO = 5 2*1 %-The chromic acid used in our experiments was obtained by adding sulphuric acid to bi-chromate of potash. It was in beautiful distinct crystals of nearly a quarter of an inch in length being the finest and purest specimen which we have obtained in many prepara-tions of this acid.The half of an equivalent 26.09 grains dissolved in 1000 of water with an increase of 9.0 at 72'; this gives 18.0 as the volume of chromic acid in solution. The same quantity of acid thrown into the solution from which it had crystallized gave an increase of 9.7 and 9% in two experiments. 1. Chromic acid volume 19.4 ... 2.690 11. .*. ... 19-6 ... 2*663 Mean . . 19-5 ... 2.676 Yellow Chromate of Potash KO CrO,= 99*50.-On dis-solving 5 0 grains of this salt in 1000 grains of water the in-crease mas 9.0 at a temperature of 58'; this gives 17.9 as the volume of the equivalent in solution.The mean result of ten experiments on immersing 49-7 Atomic Volume and Spec@ Gravity. 449 grains in turpentine was an increase of 1855 which gives 37.1 for the volume of the equivalent and 2.682 as the spe-cific gravity of the salt. Sesquichromate of Potash 2 K 0 SCrO = 25 1 *09.-This salt which will be described in a future communication by one of us is obtained by boiling a solution of bichromate of potash with an excess of finely pounded litharge. The oxide of lead removes only one-focrth of the chromic acid of the bichromate and the solution on cooling deposits the sesqui-chromate in flattened prisms of a paler but more resplendent colour than the bichromate of potash. On dissolving the fourth part of an equivalent 62-77 grains in 1000 grains of water the increase in four experiments at 58' was exactly 18.0 j this gives 72.0 as the volume of the equivalent in solu-tion.The mean of six experiments placing the fourth of an equivalent 62.17 grains in turpentine was an increase of 23.7 which gives 94.8 as the volume of the equivalent and 2.648 as the specific gravity of the salt. Bichrornate of Potash KO ZCrO = 15lmi0.-On dis-solving 76 grains of this salt in 1000 grains of water an in-crease of 22.5 and 23.0 were obtained in two experiments at 60' and 65'. I. KO 2 CrO, vol. in solution 44.9 45*8 Mean . . 45-3 - 11. ... 0.. Half an equivalent of the salt 75*84 grains immersed in turpentine gave an increase the mean of ten experiments of 28'9 which gives 57.8 as the volume of an equivalent and 2%24 as the specific gravity of the salt.Terchromale of Potash KO 3Cr03 = 203*92.-This salt was obtained by mixing a solution of bichromate of potash with nitric acid and crystallizing. On dissolving 51 grains of the salt in 1000 grains of water an increase was occasioned of 18*0 at 60'; this gives 71*9 as the volume of the equiva-lent in solution. On immersing 50.98 grains in turpentine the increase was 19.3 in two experiments and 19% in a third trial. I. KO 3Cr03 vol. of salt 77*2 ... 2'641 11. ... ... 7 7 9 ... 2.641 111. ... ... 76*O ... 2.683 Mean . . 76.8 ... 2.655 Bichromate of Chloride of Potassium KC1 + ZCrO,= 179*OS.-The fourth part of an equivalent 44.77 grains bein 450 Messrs. Playfair and Joule on dissolved in 1000 grains measure of a dilute solution of mu-riatic acid gave an increase of 15.7 in two experiments at 57' ; this result makes the volume of an equivalent in solution 62.8.The mean of various experiments on this salt gave an in-crease of 18-15 on immersing the above quantity of salt in turpentine which yields 72.6 as the volume of the equivalent, and 2.466 as the specific gravity of the salt. The results now described show that the chromates form a group different from the classes of salts hitherto given. TABLE X.-Showing the Volumes occupied by certain Chromates. 2 19.5 37-1 94.8 57.8 76.8 72.6 Designation. - & -T v d k 8 a g + " a -2.676 2.682 2.648 2.624 2.655 2.466 Volume of salt in solution. Chromic acid ............... Chromate of potash ......Sesquichromate of potash. Bichromate'of Dotash ...... CrO, KO CrO, 2K0,3Cr03 KO. 2Cr0, Terchromate oi potash Bichromate of chloride of potassium ......... 52.19 18.0 99.50 17.9 251.07 72.0 151*70 45.3 203.92 71.9 179.08 62-8 18.0 18.0 72.0 45 72 63 An inspection of the previous table will show clearly that the chromates differ fi-om the salts described in the former sections. I n the volumes in solution there is no difference; they are multiples of 9 arid follow the usual law of the sum of the volumes being made up of the volumes of the consti-tuents of the salt. Chromate of potash possesses two volumes in solution exactly as is the case with its analogue sulphate of potash. The latter salt affects three volumes in the solid state, and so naturally should chromate of potash.In bichromate of potash we see these three volumes appearing in solution, united to two volumes possessed by the chromic acid attached to the chromate of potash; in sesquichromate of potash they again reappear and so also in terchromate of potash. The fact that the number of volumes possessed in the solid state by the lowest member of a series of salts passes over into the higher members when in solution finds examples in the car-bonates and oxalates and is not peculiar to the chromates. The solid volumes of the chromates possess decided peculi-arities being neither multiples of' 11 nor of 9.8. Chromic aci Atomic Volzcme and Speci$c Gravity. 45 1 itself is obviously twice the volume of ice 9% x 2 = 19*6 the experimental number being 19.5.But all the other salts iii this group refuse to arrange themselves under either of the heads which we have found to explain most of the salts in the previous sections. I n an exception of this kind we are en-titled to make an assumption which will in all probability be near the truth if by means of it we can bring into one uni-form system a whole group of anomalous salts. Sesqui-chromate of potash is of great importance in the history of the chromates from its frequent occurrence although hitherto it has been altogether neglected by chemists. Chromic acid is actually able 40 displace sulphuric acid from sulphate of potash in order to gratify its love for the potash in the pecu-liar condition of the sesquichromate.I n numerous instances of decomposition as ~7ill be pointed out by one of us in an-other paper this sesquichromate appears. The sesquichro-mate is not formed readily if indeed it is ever formed by crystallizing chromate of potash with chromic acid in the proportion of sesquichromate the result being bichromate of potash and chromate of potash which crystallize separately. Here then is a remarkable point in the constitution of the chromates which can only be explained by supposing that sesquichromate of potash contains a double atom of chromate of potash united to one of chromic acid. The decomposition of bichromate of potash by oxide of lead necessarily implies that its atom should also be doubled ; 2K0 3Cr0 + CrO, boiled with litharge gives ZKO 3Cr0 + PbO CrO,.We have found the volume of KO CrO to be 37*1 not 33.0 as in the case of sulphate of potash. Karsten obtained the specigc gravity 2*640 which gives the volume 37.6; and Thomson states the specific gravity to be 2.612 which gives the volume the mean of all these experiments is 37'6, which multiplied by 2 for the reasons already stated gives as the volume of 2(KO CrOJ 75.2. The natural volume of chromate of potash deduced from its analogyto sulphate of pot-ash would be 11 x 3 or on the double atom 11 x 6=66. Now, the assumption we make to explain this class of salts is that the double atom of chromate of potash enjoys its anomalous character by adding to its natural volume the volume of ice, thus 66*0+9-8=75*8 which is not very far from the volume ascertained by experiment.This assumption of a volume of ice in addition to other volumes of 11 has been shown to exist in the magnesian suiphates and therefore its hypothe-tical existence in the chromates is by no means extravagant. Sesquichromate of potash must then be the double chromate of potash united to an equivalent of chromic acid 75-8 + 19-452 Messrs. Playhir and Joule on =95*4 which is not very far from 94.8 the volume deter-mined by experiment. Bichromate of potash would consist of a double atom of chromate of potash and 2 of chromic acid or 75.8 + 39*2 = 1 15-0 which agrees pretty closely with the experimental determination of 115*6 ; and terchromate of potash in like manner is 1 atom of double chromate of pot-ash with 4 of chromic acid or 75% + 78'4 = 154'2 which is almost exactly the same as 154*4 found in the two conaecu-tive experiments and not far distant from 153'6 the meanof the three experiments.This view receives confirmation from the volume of Peli-got's salt which certainly consists of the volume of KCl, when in combination added to that of 2 atoms of chromic acid 33.0 + 39*2 = 722 a number very close to the experi-mental result 72.6. It is quite true that we have made a gratuitous assumption at the outset of our explanation; but it is not surprising to find an unusual law prevailing in a class of salts so anomalous as the chromates. When the experi-mental numbers and those calculated on the assumption are so near as we have shown them to be there is we think a good argument for the truth of the hypothesis.TABLE X.A. 19.6 75.8 95.4 115.0 154.2 72.2 -Chromic acid ......... ........./ CrOs 1 19.5 -2,663 2.627 2.658 2.638 2.644 2.480 ... { Bichromate of potash Terchromate of potash ... { Bichromate of chloride of ............... potassium I-(2K0,2Cr03) 115.6 +2CrOs (2 yiEF$)3) 15 4.4 KC1+ Cr03 72,6 _c 5; '5 E $a"& ' 8 $ g!! ib -2.676 2.646 2.648 2.624 8.64 1 2466 A singular result obtained in the examination of the anhy-drous double sulphates seems to be explained by the behaviour of the chromates. We found sulphate of copper and potash and sulphate of magnesia and potash to affect a volume of 59*8 instead of 55*0 and we ascertained by many experiments, that this high number was not due to an error of observation.Now if we suppose the KO SO in these salts to behave like KO CrO in assuming one volume of ice on the double atom, then 2K0 SO,= 75*8 + 2M0 SO = 44.0 = 7 = 59.9, 119* Atomic VoLurne and Spec@ Gravity. 453 a number almost identical with the experimental result. On this view then anhydrous double sulphates are constituted on the type of red chromate of potash the two volumes of CrO being replaced by the two volumes of MO SO,. An-hydrous alum was found to have a volume of 116*4 instead of 11 1'4 but would be reconciled with theory if we supposed it to contain the peculiar KO SO analogous to KO CrO,; in this case the theoretical volume would be 116-3. SECTION VI. Carbonates. Carbonate of Potash KO CO,= 69*4.-On dissolving 34*7 grains of carbonate of potash in 1000 grains of water the in-crease was 4.6 at 62'; the atomic volume in solution is there-fore 9.2.The same quantity of salt thrown into turpentine caused in various experiments an increase of 16.5 ; this makes the volume of the equivalent 33*0 and the specific gravity of the salt 2.103. Bicarbonate of Potash KO HO ZCO = 100*6.-The fourth part of an equivalent (25'1 grains) dissolved in 1000 grains of water at 61' with an increase of 8*9 and in another experiment of 9.0. The mean of these results 8-95 gives as the volume of the equivalent in solution 35% The same quantity of salt thrown into turpentine gave an increase of 12-0 in various experiments which gives for the specific volume of the salt 48-0 and for its specific gravity 2*092.As this salt was one of the very few substances used in this inquiry not prepared by ourselves we take the mean of our own result and the only other recorded specific gravity of which we are aware viz. that by Gmelin 29012 and adopt 49.0 as the correct volume and 2-052 as the specific gravity. Bicarbonate OJ' Ammmia HO NN,O 2C02= 79*3.-This salt was made by exposing the carbonate of the shops to the air until it ceased to emit smell and then crystallizing the remainder. On dissolving 19.82 grains the fourth of an equivalent in 1000 grains of water the increase was 9*0 at 55O and 9.4 in another experiment at 62'. The mean result gives 36% as the volume of the salt in solution. On immersing 19.82 grains of the salt in turpentine an in-crease of 12*5 was effected which gives as the volume of the salt 50'0 and for its specific gravity 1*586.Bicarbonate of Soda NaO HO 2 C 0 2 = 84*64.-On dis-solving 42*32 grains of this salt in 1000 grains of water at 67' an increase of 9.0 was obtained ; this gives for the volume of an equivalent in solution 18% On immersing the same quantity of salt in turpentine the increase was 19.4 and 19.2 in two experiments 454 Messrs. Playfair and Joule on I. NaO HO SCO, vol. of salt 38*8 *.. 2.181 11. ... ... 38*4 ... 2.204 Mean . . 38.6 ... 2*192 Although we have examined other carbonates we purposely avoid bringing them into the present paper because they in-volve considerations upon which we are at present engaged in minute study and do not wish to hazard without sufficient proof.We subjoin the few carbonates here examined in a tabular form. TABLE X1.-Showing the Volumes occupied by the Alkaline Carbonates. 1 ~ 0 1 . in solution. Volume of salt. I Designation. Name. Carbonate of potash ...... Carbonate of soda ......... Bicarbonate of potash . .( Bicarbonate of soda ...... Bicarbonate of ammonia I 1-1-HO NaO 2C0 84.64 '18.0 H0,NH40,2C0 ?9.3 /364 1 9 33.0 ...... 22.0 4 36 49-0 2 18 38.6 4 36 50.0 The results shown in this table will appear perplexing, unless the facts already observed in the previous sections be borne in mind. We find in carbonate of' potash an astonish-ing difference between the liquid and the solid volume; and this is still more marked in the case of carbonate of soda, which ceases to occupy volume in solution.Both of these salts have 11 as the divisors of their solid volume KO CO, affecting three and NaO CO two volumes. In the last section we saw that the three volumes possessed by chromate of potash in its solid state passed over into bichromate of potash; and in bicarbonates of potash and ammonia we observe the same circumstance except that the volumes change from multiples of 11 to multiples of 9-8 and in solution are one less than in the state of a salt. It is probably owing to this circumstance that we do not in this case observe the usual increase of one volume in the ammoniacal over the corresponding salt of' pot-ash. The bicarbonates of potash soda and ammonia are pro-bably multiples of 9'8 or the volume of ice.Vol. by experiment. Bicarbonate ofpotash .49*0 .. 2-052 .. 9*8 x 5 =49*0 .. 2'052 ammonia 50*0 .. 1.586 .. 9*8 x 5 =49*0 .. 1-618 soda . .38*6 .. 2*192 .. 9.8 x 4 =39*2 .. 2.159 Vol. by theory. (-.-7 --Ap- 7 ... .. Atomic Volume and Spec@ Gravity. 455 SECTION VII. Oxalates. The oxalates offered an interesting group of salts for exa-mination especially on account of the accurate determination of their composition and hydration by Graham. Oxalate of Water HO C 0 + 2HO = 63*26.-32 grains of oxalic acid dissolved in 1000 grains of water caused an in-crease of 185 at a temperature of 55' ; the same quantity, being subjected to a second experiment caused an increase of 19; and a third experiment in which 21 grains were dis-solved in 94 ounces of water occasioned an increase of 12 at 40'.I. HO C,O + 2H0 vol. in solution 365 11. ... ... ... 37.5 111. ... ... ... 36.0 Mean . . 36% A whole equivalent thrown into turpentine caused in va-rious experiments an increase of 39.0 which gives for its specific gravity 1*622. Richter states the specific gravity to be 1'507 ; but it is impossible that he can have operated upon a pure specimen as we have repeated the experiments upon this acid very frequently. Oxalate of Potash KO C 0 + H O = 92*39.-A quan-tity of salt 425 grains being dissolved in 1000 grains of water gave an increase of 13'0 ; and the same result attended a repetition of the experiment the temperature in both cases being at 60'. KO C,O + HO vol. in solution 2 8 2 462 grains of the same salt being put into a saturated so-lution caused a rise in the stem of 22*0; a repetition of the experiment with the szme quantity gave the increase 219, the temperature in both cases being 61'.Sp. gr. ... ... ... 43.8 ... 2.109 Mean . . 43*9 ... 2.104 I. KO C 0 -+ HO vol. of salt 44-0 ... 2*100 I IT. Oxalate of Ammonia NH,O C 0 + HQ = 71*43.-Half an equivalent of this salt (35'71 grains) was dissolved in 1000 grains of water with an increase of 18*0 at a temperature of' 55'; and a repetition of the experiment with the same quan-tities and at the same temperature gave exactly the same re-sult. Chern. SOC. Mem. VOL. 11. 2 456 Messrs. Playfair and Joule on I. 11. NH,O C 0 + HO vol. in solution 36 35*71 grains being immersed in a saturated solution gave in the first experiment an increase of 24'5 in the second of 24.4; the first experiment being at 48' the second at 50'.Sp. gr. 11. ... ... .*. 48.8 ... 1*464 Mean . . 48.9 ... 1*461 Binoxalate of Potash KO C,O,+HO C,O + 2HO = 146*63.-To determine the volume of this salt 18.33 grains were dissolved in 1000 grains of water with a rise of 6.8 at a temperature of 57' ; and the same result attended a repetition of the experiment; in a third experiment 25 grains at the same temperature caused an increase of 9.0. I. NH,O C 0 -+ HO vol. of salt 49-0 ... 1-458 I. 11. Binoxalate of potash vol. in solution 54.4 111. ... ... ... 5 2-8 Mean . . 53.6 Half an equivalent of the salt (73.31 grains) being immersed in a saturated solution caused an increase of 37*4 in the first experiment and of 3'7.2 in the second the temperature in both cases being 5 5 O .Sp. gr. I. Binoxalate of potash vol. of salt 74% ... 1*960 ... ... ... 74*4 ... 1.971 Mean . . 74-6 ... 1.965 ~ 11. Ozalate of Copper and Potash KO C 0 + CuO C 0 + 2HO = 177*25.-on account of the sparing solubility of' this salt 11-08 grains or the sixteenth part of an equivalent, were dissolved in water and caused an increase of 3.4 in two experiments at a temperature of 59'. 1. 11. KO C 0 + CuO C O,+ 2H0 vol. in solution 54.4 The fourth of an equivalent (44*3 grains) placed in a satu-rated solution caused an increase in one experiment of 1 Y 5 ; in another of 18.9 ; and in a third of 19.7 ; all at a temperature varying from 54' to 57'. Sp. gr.I. Oxalate of copper and potash vol. of salt 78.0 ... 2-272 11. ... ..* ... 75.6 ... 2*344 111. .I. ... ... 78.8 ... 2.249 Mean . . 77.5 ... 2*288 Binoxalate of Ammonia NH,O C 0 t HO C 0 + 2HO = 125.69.-31'42 grains of this salt dissolved in 1000 grains of water caused in the first experiment an increase of 18*0 at 60' ; in the second of 18-2 at 61' ; in a third experiment o Atomic Volume and Specijic Gravity. 45 j 17.8 at 54'; in a fourth 42 grains dissolved in 4100 grains of water increased 24.0 at 53'. I. Binoxalate of ammonia vol. in solution 72-0 11. ... ... ... 72.8 111. ... ... ... 71*2 IV. ... ... ... 71.8 -Mean . . 71.9 The half of an equivalent (62.84 grains) being immersed in a saturated solution caused an increase of 40.3 in two ex-periments and of 40*0 in a third.Sp. gr. I. Binoxalate of ammonia vol. of salt 80*6 ... 1,559 TI. ... ... ... 80% ... 1.559 Mean . . 80.4 ... 1.563 111. e.. ... ... 80.0 ... 1-571 -Oxalate of Copper and Ammonia NH,O C 0 + CuO C203 + 2HO = 156*38.-The solution of 18.3 grains gave an in-crease of 8.6 at 65'; this gives 73.3 as the volume of this salt when in solution. On immersing 20 grains in turpentine an increase of 10*4 was obtained which gives for the volume of the equivalent 81.3 and for the specific gravity of the salt 1.923. Quadroxalate of Potash KO C 0 + 3 H 0 C O3 + 4 H 0 = 255.11.-320 grains dissolved in water gave an increase of 15% at 60'; and a second experiment in which 16 grains were dissolved in 1000 grains of' water gave the increase of 7.2 at a temperature of 44'.119.4 11. ... ... ... 114*8 Mean . . 117*1 I. Quadroxalate of potash vol. in solution 63-8 grains the fourth part of an equivalent thrown into a saturated solution caused a rise of 35.1 in two experiments. Sp. gr. I. 11. Quadroxalate of potash vol. of salt 140*4 ... 1*8l'/ Quadroxalate of Ammonia KO C 0 $ 3H0 C 0 + 4 H 0 = 234'1 5.-On dissolving 20 grains of this salt in 3500 grains of water at 50° the increase is 11.5 which gives 134.5 as the volume of the equivalent in solution. 58.5 grains of the salt thrown into a saturated solution, caused in the first experiment an increase of 36.8 in the second of 36.9 both at a temperature of 62'. Sp. gr. 11. 0.. ... ... 147.6 ... 1.586 I. Quadroxalate of ammonia vol. of salt 147.2 ...1-591 Mean . . 147'4 ... 1*589 . 2 H 458 The volumes of the oxalates can only be explained by an attentive consideration of the previous results. We have already seen numerous instances in which the primitive vo-lumes 9.8 and 11*0 become mutually convertible ; this is stri-kingly the case with the salts of the present section. Hydrated oxalic acid has a volume 9 8 x 4; oxalate of potash possesses the volume 11 x 3 and passes with this volume into the binoxalate and quadroxalate of potash the oxalic acid in the binoxalate being associated as two volumes of ice although the water of crystallization possesses the volume 11. Quadroxalate of potash is to be viewed as anhydrous binoxalate plus 2 equiv. hydrated oxalic acid the latter having become 11 x 4 instead of 9.8 x 4.The same explanation applies to the binoxalate and quadroxalate of ammonia the only difference being that anhydrous oxalate of ammonia 9.8 x 4 takes the place of oxalate of potash. On these view$ the following table is con-structed. Messrs. Playfair und Joule on 63-26 9239 71-43 146.63 TABLE XI1.-Showing the volumes occupied by certain Oxalates. 36.6 4 28.2 3 36.0 4 53.6 6 1 vol. in solution. 1 Volume in state of salt. 125.67’ 71-9 177.251 54.4 156.38 733 255.11‘ 117.1 234.15 134.5 I I I Name. 8 6 8 13 15 Oxalic acid ......... Oxalate of potash ... Oxalate of ammo-nia ............... Binoxalate of pot-ash ............... Binoxalate of am-monia.. .......... Oxalate of copper Oxalate of copper Quadroxalate of Quadroxalate of I-} 1 and potash ......} and ammonia.. . } ammonia ...... } potash ......... 36 27 36 54 72 54 72 117 135 Designation. 39.0 4 43.9 4 48.9 5 74.6’ 7 80.4 8 77.5 7 81.3 8 140.4 13 147.4 14 Formula. 110 C 03+2HO KO C O,+HO NH,O C,O,+HO KO 2C2 03+3H0 NH,O 2C2 0,$3HO KO C 0 + CuO C2 0, +2HO +2HO K04C,0,+7HO NH,O 4C2 O,+‘IHO -t c, R P Q1 a ; 2 39.2 44.0 49.0 746 808 77.0 80.8 40.6 .46*8 -The examination of the volumes occupied by the oxalates presents several points of great interest. The volume of oxalic acid itself is a multiple of the volume of ice or 9% x 4. Oxalate of potash in its solid state possesses four volumes, 11 x 4 but loses one volume on passing into solution as usually is the case with neutral salts of potash.As one o Atomic Volume and Specijc Gravity. 45 9 these volumes is due to its combined water the proper num-ber of volumes in anhydrpus oxalate of potash is three arid these it carries into binoxalate of potash which is therefore a simple combination of oxalate of potash and hydrated oxalic acid the crystalline water of the latter having assumed the volume 1 1. I n solution. As a salt. KO,C,O . . . . . 18 ... 33-0 HO,C,O + 2HO . . 36 ... 41% Binoxa,late of potash . . . 54 ... 74*6 The only difference between the volumes of this salt and those of its constituents when uncombined is that the cry-stalline water of the hydrated oxalic acid has assumed the volume 11.Quadroxalate of potash consists of anhydrous binoxalate of potash united to hydrated oxalic acid as Gra-ham has already announced in his researches on the oxalates. The three volumes. affected by oxalate of potash in its solid state pass into solution with it in quadroxalate of potash just as we saw in the case of chromate and bichromate of potash; and the attached oxalic acid affects 11 x 4 instead of 9.8 x 4. I. Anhydrous binoxalate of potash 45 ... 52'6 11. Hydrated oxalic acid . . . . 72 ... 88.0 Quadroxalate of potash . . . 117 ... 140% The assumption of two volumes in solution above those of binoxalate of potash was already characteristic of binoxalate of ammonia and the same increase is seen in the quadroxalate, showing clearly that that salt must contain its ammonia quasi binoxalate and not as oxalate of ammonia.It is very possible that the volumes in solution of quadroxalate of ammonia should be 14 instead of 15 but the temperature 31° at which it comes out 14 volumes is so low that it is more natural to keep the volumes we have given in the table. It is interesting to observe how closely oxalate of copper relates itself to oxalate of water. -I n solution. As a salt. -Volumes Volumes in solution. as salt. Oxalate of copper and potash . 6 ... 7 ... water and potash . 6 ... 7 ... copper and ammonia 8 ... 8 ... water and ammonia. 8 ... 8 Thus even in the apparently anomalous behaviour of bin-oxalate of ammonia in assuming two volumes more than the corresponding salt of potash we find oxalate of copper and ammonia imitating its example.The reason of their increase will be explained in the next section 460 Messrs. Playfair and Joule on SECTION VITI. Subsalts and Ammonilical Salts. The salts which we have hitherto examined have been those soluble in water and having a constitution to a certain degree well-defined. We have now to consider the insoluble sub-salts and in some cases their neutral insoluble types and also to ascertain how far the results thus obtained serve to throw light on the constitution of ammoniacal salts. Subsukhate of Copper CuO SO, 4 H 0 + 3CuO = 234*9. -This well-known salt was made by adding ammonia to a solution of sulphate of copper. The fourth part of an equi-valent 58-7 grains thrown into water caused an increase of 19.1 and 19.0 in two successive experiments.Sp. gr. I. Subsulphate of copper vol. of salt 76*4 ... 3*074 11. ... ... 76.0 ... 3*090 Mean . . 76.2 ... 3*082 Subsubhate of Zinc ZnO SO, 32110 4 H 0 = 237-3.-This salt is apt to combine with more water than four atoms, but may be obtained with four by drying at 212". On placing 29.66 grains the eighth part of an equivalent in turpentine, an increase of 995 was obtained; and on treating 22-8 in a similar manner the rise in the stem was 7.3. Both of these experiments exactly agree in making-Sp. gr. Subsulphate of zinc vol. of salt 76.0 ... 3.122 Subhate of Protoxide of Mercury Hg,O SO = 251.0.-This salt was prepared in the usual way by digesting one part of mercury in 14 part of sulphuric acid. The fourth of an equivalent 62-75 grains thrown into turpentine increased 8*3.Sp. gr. Hg,O SO, vol. of salt 339 ... 7-560 Suljdiate of Peroxide of Mercury HgO SO = 149*6.-The salt used in the experiment was prepared by heatingfive parts of sulphuric acid mixed with a little nitric acid with four parts of mercury until the whole became a dry saline mass. On immersing 37.5 grains of the salt thus prepared in tur-pentine an increase of 5% was obtained which gives 23.1 for the volume of the equivalent and 6*466 for the specific gra-vity of the salt. Subsulphate of Mercury NgO SO + 2HgO =368*46.-The last salt thrown into water and washed with warm water is converted into the beautiful yellow powder known as tur Atomic Volume and Specijk Gravity. 461 peth mineral.On throwing 57.4 grains of this salt thus pre-pared into water an increase of 6.9 was obtained which gives 4 4 3 as the volume of the equivalent and 8-319 as the spe-cific gravity of the salt. Chromate of Lead PbO CrO = 16397.-On throwing 81-98 grains of the chromate of lead previously well-dried, into turpentine an increase of 14.5 was effected; this gives 29*0 as the volume of the equivalent and 5*653 as the specific gravity of the salt. Subcl'romate of Lead PbO CrO + PbO = 275*7.-This salt was prepared by projecting chromate of lead into melted nitre and afterwards washing out all soluble matter. On im-mersing 68.92 graias the fourth part of an equivalent an in-crease of 11*0 was obtained in two experiments. This gives 4 4 ~ 0 for the volume of the equivalent and 6.266 as the spe-oific gravity of the salt.Sesquibasic Chromate of Lead Z(Pb0 CrO,) + PbO = 439*67.-The mineral melanchroit is of the composition ex-pressed by the above formula and has a specific gravity of 5.75 according to Hermann ; this gives the number 76.5 as the atomic volume of the compound. Subnitrate of Copper CuO NO, HO 2CuO= 18Plr.-The fourth part of an equivalent 45'54 grains caused an in-crease of 16.5 in two experiments and of 16*4 in a third. Sp. gr. I. CuO NO, HO + ZCuO vol. of salt 66.0 ... 2-760 11. ... ... ... 66-0 ... 2.760 ... ... ... 65*6 ... 2.777 111. Mean . . 65-87 ... 2-765 A Subnitrate of Bismuth BiO NO, HO + ZBiO = 30~4. T h i s salt was prepared in the same manner as subnitrate of copper viz. by heating the nitrate to 400' or 500'.The fourth part of an equivalent 75*1 grains thrown into water caused, in various experiments an increase of 165 which gives 66-0 as the atomic volume and 4551 as the specific gravity of the salt. B. Subnitrate of -Bismuth BiO NO + 2BiO = 291.4.-This salt was prepared by adding nitrate of bismuth to a large quantity of water ; the white powder which falls by this treatment is composed according to Phillips of three equiva-lents of oxide of bismuth united to one of nitric acid. It is therefore the same salt as the one last described deprived of its constitutional water. On immersing 72.85 grains of the salt in water a rise in the stem of 13.9 was effected and 36.42 grains treated in the same way gave an increase of 6.9. -463 Messrs.Playfair and Joule on Sp. gr. I. 3Bi0 NO, vol. of salt 55*6 ... 5-241 55-2 ... 5*279 Mean . . 55.4 ... 5*269 - 11. ... ... Subnitrate of Mercury HgO NO HO + 2Hg0 = 391.49. -This salt was obtained in a yellow powder by adding the crystallized subnitrate of mercury to water and washing it, according to the directions of Kane with hot but not boiling water. The fourth part of an equivalent 97-87 grains thrown into turpentine caused an increase of 16'4 which gives 65.6 as the atomic volume of the salt and 5*967 as the specific gravity. Arnrnoniacal Sutphate of Copper CuO SO HO + 2NH,= 123*O.-This salt has already been described in a previous section; it had a volume of 54.0 or 9 x 6 in a state of solu-tion and of 68.6 or 9-8 x 7 in the solid state.The salt exa-mined in that case was in fine large indigo blue crystals and was prepared by ourselves. Another portion made by Mr. Morson in small crystals we found to possess a volume of 68.0 and specific gravity of 1.809. When this salt is heated it loses one equivalent of water and one of ammonia being converted into a green powder the formula of which is CuO, SO + NH,; 24.27 grains of this thrown into turpentine, caused an increase of 9.8 which gives 39.2 as the volume of the equivalent and 2.476 as the specific gravity of the salt. The latter salt on being moistened with water absorbs three equivalents and therefore assumes the atomic weight of 124*07; the fourth part of which 31.0 grains thrown into turpentine caused an increase of 15*9 making the atomic volume of CuO SO + NH + 3H0 63.6 and its specific gravity 1*950.Ammonia-Sulphate of Zinc.-Kane describes several am-monia-sulphates of zinc obtained by passing a stream of am-monia through a hot solution of sulphate of zinc until the precipitate at first formed is redissolved. The solution thus obtained deposited transparent crystals in a few hours but these effloresced so quickly after being dried that we did not determine their specific gravity. The effloresced crystals have according to Kane the formula-ZnO SO + 2 NH + 2 HO = 132.8. We fear however that we have not been successful in pro-curing this salt in its proper state as the determination of its volume varied between 57.5 and 64.0 results so discordaut, that it would not be safe to take their mean as a correct re-sult.On heating this salt it loses water andammonia bein Atomic Volume and Specijic Gravity. 463 converted into ZnO SO,+NH,; 26.7 grains of which (the fourth of an equivalent) thrown into turpentine caused an increase of 20'8 which gives 39.5 as the volume of the salt, and 2.479 for its specific gravity. Ammonia-Sulphate @Mercury HgO SO + HgAd + 2Hg0 =486*0.-This salt which Kane calls the Ammonia Turpeth, was prepared by heating turpeth mineral with ammonia un-til it became changed to a heavy white powder. The eighth part of an equivalent 60'75 grains immersed in water caused an increase of 8.3 i n two experiments ; this makes the volume of the compound 66.4 and its specific weight 7.319. Ammonia-Sulphate of Silver Ago SO + ZNH = 190*86.-This salt was obtained in the usual way by dissolving sul-phate of silver in ammonia and crystallizing. The first speci-men tried was in small indistinct crystals in the second in-stance the crystals were large and well-defined. 2'262 grains gave an increase of 8:6 and 37*7 grains of the better specimen of salt gave the increase 13.2. Sp. gr. I. Ago SO + ZNH, vol. of salt 64.0 ... 2.979 11. ... e.. ... 66% ... 2*857 Mean . . 65-4 ... 3.918 Ammonia-Chromate of Silver Ago CrO + 2NH = 202% -This salt was obtained in fine large crystals in the same manner as the last salt. On immersing 25*35 grains in tur-pentine the increase was 8.3 and on treating 50*7 grains in the same way the increase was 16-5. Sp. gr. I. Ago CrO,+ SNH, vol. of salt 66.4 ...3*054 11. ... ... ... 66.0 ... 3073 Mean . . 66*2 ... 3*063 Ammonia-Nitrate of Copper CuO NO + 2NH = 128.4. -On dissolving 64.2 grains half an equivalent in 1000 grains of water the increase was 32.0 in two experiments at a tem-perature of 60'; this makes the atomic volume in solution 64*0. On putting the same quantity into turpentine there was a rise in the stem in three experiments of 34-0 34.0, and 34.8. Sp. gr. I. CuO NO + 2NH, vol. of salt 68*0 ... 1.888 11. ... ... ... 68*0 ... 1.888 ... ... ... 69.6 ... 1.845 Mean . . 685 ... 1'874 - 111. Ammonia-Sub-Nitrate of Mercury HgO NO + 2HgO + NH = 399*7.-This salt was prepared by adding a dilut 464 Messrs. Playfair am? Joule on solution of ammonia to nitrate of mercury and was of a pure milk-white colour as described by Kane.On throwing 40 grains of this compound into water an increase of 6.7 was obtained; this gives a volume of 67-0 on the equivalent and 5-970 as the specific gravity of the salt. Chloride of Copper CuCl= 67*18.-The volume of hydrated chloride of copper was shown to be 33 or 3 x 11 ; but we have not yet examined the bulk occupied by the anhydrous chlo-ride. The chloride was deprived of its water by a heat con-siderably below that of redness in order to prevent the forma-tion of any sub-chloride. On throwing 33.59 grains or half an equivalent into turpentine the increase in two experiments was exactly l l * O which gives 22*0 as the volume of the salt, and 3.054 as its specific gravity. Ammonia-Chloride of Copper CuCl + 2NH + HO = 110*3.-This salt was made by passing a stream of ammonia through a solution of chloride of copper until the precipitate formed had completely redissolved. The crystals which deposited as the solution cooled were dried in a receiver containing slaked lime so as to prevent the carbonic acid of the atmosphere acting upon the ammonia; but in spite of this precaution the crystals had slightly effloresced on the surface. The efflo-resced matter was removed and the pure crystals employed. 27*6 grains of them when thrown into turpentine produced in two experiments an increase of 16.5 making the volume of the salt 66*0 and its specific gravity 1*672. On dissolving the same quantity of salt 21-6 grains in 1000 grains of water, the rise was 15*9 a t 62' making the volume of the salt when in solution 63.6.On exposing this salt to heat water and ammonia are ex-pelled and a green powder remains having the formula CuCl +NH,. 21.07 grains of this salt thrown into turpentine pro-duced an increase of 9-6 making the volume of the equiva-lent 38.4 and the specific gravity of the salt 2.194. Subchloride of Copper Cu,Cl = 98*89.-The subchloride used in the experiment was made by adding protochloride of tin to a solution of chloride of copper. During the desicca-tion of the salt it became slightly green showing that a little chloride had been formed by the absorption of oxygen; but the change was so slight as probably not to interfere mate-rially with the result; 48-2 grains thrown into turpentine, caused an increase of 12*5 which gives 29.2 as the volume, and 3.376 as the specific gravity of the salt.Subchloride of Mercury Hg,Cl= 238%.-The fourth part of an equivalent 59.58 grains thrown into turpentine caused an increase of 8.3 Atomic Volume and Specijic Gravity. 465 Sp. gr. Calomel vol. of salt 3 3 2 ... 7*178 Hassenfratz states the specific gravity to be 7-276 a result very near our own determination. Subchloride und Amide of Mercury HgzC1 + Hg,Ad = 458*1.-The eighth part of an equivalent 5796 grains thrown into water caused an increase of 8.3 and 8.4 in two experi-ments. Sp. gr. I. Black compound of calomel 67*2 ... 6.816 11. ... ... 66*4 ... 6.899 Mean . . 66.8 ... 6*858 The salt used in the experiments was prepared in the usual way by acting upon calomel with ammonia.Chloride and Amide of Mercury HgCl+ HgAd=254*5.-The excellent researches of Kane so often alluded to have shown that the above formula represents the composition of white precipitate. It must be dried by a pretty strong heat, to get rid of all its hygrometric water. On projecting 63% grains the fourth of an equivalent into water an increase of 11-2 was obtained in two experiments j this gives 44.6 as the specific volume of the compound and 5.700 as its specific gravity. Basic Chloride and Amide of Mercury HgCl + HgAd + 2Hg0 = 473*S.-This yellow compound was made in the usual way by boiling white precipitate with water. On throwing 5 9 2 grains into water the rise was 8.2 in one ex-periment and 8.3 in another. Sp. gr. I. The above salt volume 65.5 ...7.220 ... ... 66*3 ... 7*132 Mean . . 65*9 ... 7*176 I_ I I 466 Messrs . Playfair and Joule on Subsulphate of zinc ......... Protosulphate of mercury ... Persulphate of mercury ...... Subsulphate of mercury ... Zhromate of lead ............ Subchromate of lead ......... Melanchroit ................. Subnitrate of copper ......... A . Subnitrate of bismuth ... TABLE XII1.-Showing the Volumes occupied by certain Subsalts and Salts of Ammonia . { Zn24\2. 3Zn0 Hg20. SO, HgO. SO, HgO. S03+2Hg0 PbO. CrOs PbO. CrO +PhO 2Pb0. 2Cr0. + PbO CuO. NO. HO+2Cu( RiO . NO. . HO+BBiC Designation . I hbsulphate of copper ...... 1 { cu2A2’ 3cu0 B . Subnitrate of bismuth ... Subpernitrate of mercury .. 1 { “f$);:B Ho 1 BiO. go. +iBiO 8 .Ammonia-sulphate of copper ..................... B . A-mmonia-sulphate of copper ..................... Hydrate of ammonia-sul-phate of copper ......... } Ammonia-sulphate of zinc ... Ammonia-turpeth ........... CUO. SO.+NH. CuO. SO. + NH. ZnO. SO.. NH. c Ad+2HpO 1 HgO. so. + Hg Ammonia-sulphate of silver . AgO. SO3+”2NH. ’ Ammonia-chromate of silver Ago. CrO. +2NH3 Ammonia-nitrate of copper . I CuO. NOS+2NH. _ _ Ammonia-nitrate of mercury Chloride .................... Ammonia-chlo&e of coppei B . Ammonia-chloride of copper ..................... Subchloride and amide of mercury .................. Chloride and amide of mercury .................. Basic chloride and amide of mercury ............... I-1 1 Subchloride of copper ......Subchloride of mercury ..... , Cu C1+2NH3+H0 Cu Cl+NH. ..... Hg2 c1 Hg2 el+ Hg. Ad Hg C1+ Hg Ad HgCl+HgAd 1 +2Hg0 1 . Atomic weight . . 234.9 237.3 251.0 149-6 368.4( 163.9: 275.7 439.6: 182.1: 300.4 291-4 391*4! 123.0 974 124.0 97.8 486.0 19081 202.8 128.4 399.7 67.1 110.3 84.1 98.8 238.3 458.1 254.5 473.3 Volume in solution . . c1 3 ; S E - 0 0 .$ ;$ P .. -... ... ... ... ... ... ... ... ... ... ... ... 54 ... ... ... ... ... ... 64 ... ... 631 ... ... ... ... ... ... . J 3 . ” s E 4 0; . ... ... ... ... ... ... ... ... ... ... ... ... 6 ... ... ... ... ... * I . 7 ... .., 7 ... ..I . t d, R i 2 ... ... ... ... ... ... ... ... ... ... ... ... 54 ... ... ... ... ... ... 63 ... ... 63 ... ... ... ... ... ... 76.2 76.0 33.2 23.1 44.3 29.0 44 765 65.9 66.0 55.4 65.6 68.7 39.2 63% 39.5 66.4 65.4 66.2 68.5 67.0 23 66 38.4 29.2 339 66.8 44.6 659 Volume of salt . . J 3 0 E i!i . I . 7 7 3 2 4 4 7 6 6 5 6 I .. I .. .. 6 6 6 ... ... 2 6 ... ... 3 6 4 6 -. A 9 a 0 R 3 B 77 77 33 22 44 44 77 66 66 55 66 . ... ... ... ... ... 66 66 65 ... ... 22 66 ... ... 33 66 44 66 2 P ‘5 9 a6 a & 3.051 3.085 7*60t 6+30( 8.374 6.26t 5-71( 2-76( 4.55 1 5-29) 5.935 ...... ... ... ... 7.36; 2*89( 3-07; ... ... 3.051 1.67 ... 7:i;2: 6.94‘ 5.781 7-1 Atomic Voluine and Speci-Jic Gravity. 467 The important researches of Graham have shown that water plays a most important part in the constitution of salts; and that salts with an excess of base may be viewed as hydrates, in which oxide of hydrogen becomes replaced by a metallic oxide. The previous experiments s i l l be found to give this theory the fullest confirmation. Sulphate of zinc crystallizes with seven atoms of water and affects a volume of 74-6 ; and sulphate of copper assumes the same state of hydration when crystallized with the latter salt although per se it assumes only five atoms.Placing together the subsulphates and hy-drated sulphates of these metals we perceive not only a close similarity in their formulae but also in their volumes as ascer-tained by experiment. Difference. 1.4 1.6 ZnO SO, 3HO,4HO vol. 74*6 ) Zn0,-SO, 3Zn0,4HO .. 76.0 CuO SO, 3HO,4HO vol. 74.6-CuO SO3,.3Cu0 4H0 .. 769) The difference between the two states of the sulphates is probably greater as stated than it actually is. We have al-ready shown that the magnesian sulphates with seven atoms of water do not possess a volume of 77.0 because two of the atoms possess a volume of 9-8 instead of 11.0 ; and perhaps a similar circumstance tends to reduce the volume of the sub-sulphates. Similar instances of replacement of water by a metallic oxide are seen in other parts of the table.We have already shown that nitrates of copper and bismuth possess a volume of 5893 or 9% x 6. We have also seen instances in which 9-8 the volume of ice in feeble compounds be-came changed into the volume 11 when the salt entered into combination. I n this point of view the subsalts MO NO + HO + 2MO become assimilated to the hydrated nitrates MO NO + HO + ZHO the number of volumes in both cases being the same the only difference being that in the former case the salts are multiples of 11 and in the latter of 9.8 or the volume of ice. The hydrated type affects six volumes and so do the subnitrates as will be seen by the following table. CuO NO, HO + ZCuO volume 65*9 or 11 x 6 BiO NO, H 0 + ZBiO ... 66-0 ... 11 x 6 HgO NO, HO+ZHgO ...65.6 ... 11 x 6 We have furt-ier evidence of the equivalency of water to the metallic oxide in anhydrous nitrate of bismuth which has a volume of 55.0 or 66- 11 ; the formula for the salt being BiO NO,+ aBiO. The conversion of the volume 9.8 into 1 468 Messrs. Playfair and Joule on is by no means uncommon and is again seen in the subchro-mates of lead. Chromate of lead has a volume sensibly the multiple of 9.8. BY experiment. By calculation. - r-Chromate of lead 29-0 ... 5.653 9.8 x 3=29.4 ... 5.577 Boullay gives the specific gravity of oxide of lead as 9.5, which indicates the volume 11-7 a number not far from 11, which we take as the unit volume. Subchromate of lead con-sists of one equivalent of the neutral chromate united to one of oxide of lead but the three volumes of ice in the former have changed in the subsalt to 11 x 3 and the same is the case in the mineral melanchroit which contains two equivalents of chromate of lead united to one of oxide of lead.Subchromate of lead PbO CrO + PbO = 44 or 11 x 4 Melanchroit 2 (PbO CrO,) + PbO = 76-5 or 11 x 7 In these salts we clearly see that oxide of lead takes up the volume and plays the part of an atom of water although we are ignorant of their hydrated types. The same function of an oxide is seen in turpeth mineral in which the ZHgO, attached to HgO SO, assumes the volume of two atoms of water 22 + 22 =44. There can be little doubt from the pre-vious examples of the equivalency of CuO ZnO BiO HgO, and PbO not only to each other but also to water ; and this will be still more strongly seen by placing the volumes of these and other anhydrous magnesian sulphates along with the vo-lume of sulphate of water itself as deduced from bisulphate of potash.... Sulphate of Water vol. by experiment 22.0 ... Zinc ... 21.8 ... Iron ... 24 -0 ... Cobalt ... 22*0 ... Copper ... 22*0 ... Mercury ... 23*1 The only cases in which there is an appreciable difference froni sulphate of water are those of sulphates of iron and mercury neither of which salts can be obtained without diffi-culty perfectly pure in an anhydrous state. But if the equivalency of the magnesian metals to each other and to hydrogen be left in any doubt by the preceding table this doubt would be entirely removed by a consideration of the magnesian chlorides.The strongest muriatic acid ob-tained has according to Thomson a specific gravity of 1*203, and contains 40*66 per cent. of dry muriatic acid; which is equal to 5-91 obviously six atoms of water to one of muriati Atomic Volume and Specij5c Gravity. 469 acid as pointed out by Kane. The atomic weight of this compound divided by its specific gr'avity is - - 7 5 9 , which is not far from 72*0 or 9 x 8 considering that the re-sult remains uncorrected for expansion ; this gives a volume of 18.0 or 9 x 2 for muriatic acid. The acid which possesses a constant boiling-point and distils over unchanged has a spe-cific gravity of 1.094 and contains 1919 per cent. of absolute acid according to Davy and 20-44 per cent. according to Thomson. The mean of their results indicates the acid to 180*47 contain lg4 or nearly 16 atoms of water.Now - 1.094 = 165 which is not far from 162 the volume of 9 x 18 ma-king for the volume of muriatic acid in strong solutions 18.0 or 9 x 2 a result the same as that obtained by the last cal-culation. These results and that given in aprevious section, along with the fact that hydrochloric acid gas has twice the volume of steam leave no doubt that muriatic acid affects two volumes; and converting the liquid into the solid volume we have a volume of 22% or 11 x 2 as the atomic volume of solid muriatic acid. By contrasting this volume with the experi-mental results on the magnesian chlorides we find a very great similarity. 90.4'1 1903 -Chloride of Hydrogen volume 22.0 or 11 x 2 ...Cobalt ... 22*2 0 .. ... Calcium ... 22*4 0.. ... Magnesium ... 22*1 0.. ... Copper ... 22.0 ... . .. Mercury ... 22*0 ... I n dilute solutions muriatic acid affects only one volume, and this has been shown to be also the case with chlorides of copper arid cobalt. Whether nitrate of water and nitrate of a magnesian oxide possess the same volume it is difficult to decide. Nitrate of water in the acid of specific gravity 1.42 seems to affect four volumes and this acid HO NO, + 3HO is constituted on the same type as CuO NO + 3HO ; yet 90.2 63 - = - = 7 which gives four volumes for HO NO, while 1-42 9 nitrate of copper certainly does not possess more than three volgmes. Nitrate of water calculated on weak aeids has ;three volumes; but there being no good fixed point upon which to make the calculation we must leave at present this point undetermined.An important question now arises as to the truth of the supposition that two atoms of a magnesian metal are equal t 470 Messrs. Playfair and Joule on one of the family of which potassium stands as the type In calomel and chloride of ammonium we have a direct case in point and the similarity of volumes is very striking. Di fE Calomel Hg,Cl . . . . . . . . 33-2 34*01-0.8 Chloride of ammonium NH4C1 . . . I n this case we have taken chloride of ammonium because KCI assumes the volume of four atoms of ice. Subchloride of copper like NH4C1 possesses three volumes, according to Karsten's experiments and our own but these three volumes are multiples of 9.8 and not of 11.0.Subchloride of copper vol. 29'2 3.376 of mercury and sulphate of potash. By experiment. By calculation. +-7 1 A > 9 8 x 3 = 29*4 3'363 Another illustration is furnished in sulphate of protoxide DiE Protosulphate of mercury vol. 33.20 Sulphate ofpotash . . . . 33005}0*15 These are instances in which two atoms of a magnesian metal are at once shown to be equivalent to one of a metal of the potash family; but it does not thereby preclude the pos-sibility of two atoms of a magnesian oxide being equivalent to one atom of potash. For example a magnesian sulphate, MgO SO, affects a volume 22 or 11 x 2 while the same salt united to an atom of constitutional water has the volume 33 or MgO S0,HO becomes equal to KO SO, which also possesses a volume of 33.The most striking case how-ever is seen when crystallized subnitrate of lead is compared with nitrate of potash. Nitrate of potash KO NO, vol. . . . . 49-0 Subnitrate of lead PbO NO + PbO vol. . 49-0 The fact that two atoms of a magnesian oxide are equiva-lent to one of potash appears to find its explanation in the circumstance that we unifbrnily find the salt of potash assu-ming one volume greater than the corresponding salt of mag-nesia. Hence as the volume of the oxides corresponding to the latter body is equal to unity the equivalency of two of their atoms to one of potash becomes a matter of necessity. To sum up these remarks we conceive (I.) that Graham has taken the correct view in supposing subsalts to represent hydrated salts in which water has been replaced by a me-tallic oxide; and (2.) that the volume of two atoms of a metal of the magnesian family in which we include hydrogen is equal in volume to one of the potassium group; or two atom Atomic Volume and Specific Gravity.471 of the former oxide when combined to one of the latter. We are now in a condition to consider the salts of ammonia. It is quite unnecessary to remind chemists that there are two rival theories regarding the constitution of ammoniacal salts. One of them proposed by the profound Berzelius is that the salts of ammonia contain a hypothetical radical termed ammonium conaisting of one equivalent of nitrogen and four equivalents of hydrogen. Sulphate of ammonia is to be viewed as sulphate of oxide of ammonium the latter hypothetical body being equivalent to potash ; and hence the isomorphism between the salts of potash and ammonia.The other view of the constitution of ammonia is that proposed by Kane and so elaborately supported by him in his paper on subsalts and ammoniacal compounds*. Dr. Kane sup-poses that an ammoniacal salt is formed on the type of a rnagiiesian salt carrying along with it constitutional water. Sulphate of copper . . . CuO HO SO, Sulphate of ammonia . . HO NH,H SO, On this view amide of hydrogen is equivalent to and plays the part of an atom of water. If this be the case amidogene must be analogous to oxygen and ammonia and a magnesian oxide must possess the same atomic volume. At present all this is purely hypothetical and must be subjected to the test of experiment before we can admit it as a safe foundation on which to rear a theory.The means of deciding this question seemed to present itself in an examination of the amides of mercury and of the crystallized salts of copper and zinc in which the ammonia is present quasi ammonia; and such compounds have been described in the beautiful researches of Kane on this subject. Wohler's white precipitate HgCl +NH seems to be constituted in the most simple manner, and possesses a volume of 33.0 which deducting the volume 22.0 for HgC1 leaves 11.0 or unity as the volume of NH,. But again white precipitate HgCl + HgNH, affects a volume of 44.6 by experiment which deducting 28-0 for HgCl leaves HgNH also equal to 22.0 and yet the latter compound should correspond in volume to NH,H.The heavy yellow powder obtained by boiling white precipitate with water has a volume of 66.0 and is constituted according to the formula ( HgCl + H gAd) + 2 HgO ; so that deducting 44.0 the ascer-tained volume of the double amide and chloride 22 or 11 x 2 remains for two atoms of HgO .giving the same result as in the former subsalts viz. the equivalency of HgO to HO but not to HgNH,; and another proof of this is afforded in the * Transactions of the Ro_val Irish Academy vol. xix. part 1. Chem. Soc. Mem. VOL. 11. 2 412 Messrs. Playfair and Joule on reduction of the volume of ammonia turpeth. From this cir-cumstance the view would appear probable that amide and chloride of mercury are equivalent and hence would follow the equivalency of chlorine to amidogene.This receives fur-ther support from the volume of the double subamide and subchloride of mercury Hg,Cl+ Hg,Ad which has a volume of 66.8 according to experiment. Calomel itself possesses the volume 33-8 which deducted from that of the salt just described gives 33*6 as the volume of Hg2Acl showing the complete equivalency of the latter to the subchloride. I t has been shown that chloride of mercury and chloride of hydrogen are equivalent and it now remains to be shown by direct proof that amide of hydrogen (ammonia) is embraced in the same category. Ammonia-chloride of copper CuCl + NH, was found with a volume of W 2 or 9% x 4 ; chloride of copper itself affects two volumes which leaves for Ad H, as deduced from this salt also two volumes.But the am-monia in CuCl + 2NH,+ HO if we were to suppose the salts constituted in a manner so simple as expressed by their em-pirical formule would only have a volume of 33-0 for two atoms or 1; volume for each. In proceeding further it will be seen that we involve our-selves in inextricable difficulties if we insist upon the equiva-lency of NH,H to HO; or suppose the ammoniacal salts, such as those described to be constituted on the type of t,he hydrated salts. Thus ammonia-sulphate of copper CuO, SO,+ ZNH,+ HO has a volume of 68.6 or 9.8 x 7 in its solid state and of 54 or 9 x 6 when in solution. Deducting 19*6 for CuO SO, and 9.8 for HO there is again left 39*2 or 9% x 4 for two atoms of ammonia. The simple salt CuO SO + HN, has a volume of 39.2 which leaves 19.6 or 9.8 x 3 for one atom of amiuonia; but the same salt when combined with three atoms of water yields the volume 63.6 which would lead us to suppose that one atom of water is equal to one atom of ammonia.We also find ammonia with the volume 11 or unity when calculated from the observed volume of hy-drated sulphate of ammonia. But in the ammonia-chromate of silver Ago CrO + ZNH, and in its corresponding sul-phate we find on deducting 33.0 or 11 x 3 for the salts them-selves the residual 33.0 for two atoms of ammonia. Again, however we become perplexed by finding that the ammonia in ammonia-pernitrate of mercury possesses the volume of an atom of m-ater. Thus then by considering the volumes of the ammoniacal salts as containing their ammonia quasi ammonia, and as constituted on the type of the hydrated salts we ob-tain the contradictory and absurd result that ammonia thoug Atomic Volume and Speci$c Gravity.473 often taking a volume equal to unity sometimes possesses a volume of 14 and occasionally two volumes. It is pretty certain from these contradictory results that the salts are not constituted on the hydrated type. Graham has thrown out the ingenious idea* that the salts now referred to may actually contain an ammonium in which the fourth equivalent of hydrogen is replaced by an equivalent of a magnesian metal. Thus CuO SO + NH is constituted, according to Graham NH,Cu 0 SO, on the type of sulphate of ammonia NH,H 0 SO,. There is nothing whatever op-posed to this view in Kane's researches as he himself admits, the only difference being that he considers the said salts to contain oxide of copper and water united to amide of hydro-gen instead of to cuprammonium and oxide of ammonium, according to the views of Berzelius and Graham.While, therefore Kane admits that amide of hydrogen is very closely allied to chloride of hydrogen he claims for the former body an equally close alliance to water by asserting that it is equi-valent to a magnesian oxide although it is difficult to conceive why chloride of hydrogen has not a right to a similar claim. Amide and chloride of mercury have undoubtedly the same volume viz. 22.0 and chloride of* hydrogen also enjoys the same number; but water does not in any case do so. On this point alone then are we at issue with Kane for there are many proof's that there is extreme probabilityin the view propounded by him of the presence of NH,II and HO in ammoniacal salts.On the former view alone do we contest the accuracy of the opinion leaving for future consideration and research to which we are now tlevoting ourselves a more defined notion of the reason why NH,H and HO are equiva-lent in many instances not in all to potash. We have already stated the incongruous results which .would flow from the conception that ammonia was simply attached to the salts examined. It is true that Kane gives to some of them a con-stitution more intimate and when he does so his theory ac-cords with our results. But his conception of tlmc equivalency of NH,H to HO has led him in other.instances to attach the ammonia to the salt in place of water and it is from these cases that we dissent. If' he merely means that NH,H can replace HO in a compound as KO SO does in a rnagnesian sulphate then we cease to differ because the resulting com-pounds do not remain in strict parallelism ; the only point we argue against being that HO and NH,H are equivalent. Thus we have supposing all of them to affect the primitive volume 9.8,-* Graham's Elements of Chemistry p. 416. 2 1 4 74 Messrs. Playfair and Joule on HgO NO + HgO+ ZHO HgO NO + HO + 2HgO = 6 ... HgO NO + NH + 2HgO = 7 ... The first two members of the series have the same number of volumes because HgO and HO are equivalent and the last salt should also affect the same if NH,H = HO.But if we consider the last salt as equal to nitrate of ammonia in which HgO replaces HO then it becomes intelligible. NH,H HO NO affects 5 + 2 of HO = 7 NH,H HgO NO ... 5 + 2 of HgO = 7 = 6 VOI. On the same principle we would arrange the other ammo-niacal compounds. Thus CuO SO + NH obviously ought to be arranged NH,H CuO SO, corresponding to NH,H, HO SO, anhydrous sulphate of ammonia and both affect, as they should do on this formula four volumes. We ob-served a very decided peculiarity in sulphate of ammonia ; for while in its hydrated condition the NH,O SO could only be equal to three volumes in its anhydrous state or when in com-bination with salts it assumed four volumes. The latter pe-culiarity attends the alpha ammonia-sulphate of copper and is shared also by ammonia-sulphate of zinc while the hydrate assimilates itself to NH,O SO + HO.NH,H HO SO = 3 9 2 NH,H CUO SO = 39'2 NH,H ZnO SO = 39.2 (NH,H CUO so3=39m2) + (HOz9.8) + (NH3=19*6)=68*6 NH,H HO SO + HO = 44 (NH,H CuO SO + HO = 44) + (2HO = 19'6) = 63.6 I n ammonia-nitrate of copper we have an instance in which the ammonia may be present either as nitrate of ammonia or as ammonia; for if we suppose the volume 68.5 which obvi-ously indicates 9.8 x 7 = 68.6 to be made up of CuO NO + 2NH, we must assume that two atoms of ammonia are equal to four atoms of ice for we already have seen that CuO, NO affects three volumes. On the supposition that the com-pound contains a substance equivalent to nitrate of ammonia, the volumes are equally intelligible.NH,H HO KO = 49.0 NH,H CuO NO = 49*0 + NH,H = 19-6 = 68.6 Perhaps however the clearest instances are seen in the ammoniacal chromate and sulphate of silver. Ago CrO and Ago SO affect a volume of 9-8 x 3 and supposing a trans-formation into multiples of 11 of which we have seen fre-quent instances 2NH3=33-0 or NH,= 165 or 1; times th Atomic Volume and Specijic Gravity. 475 But on the supposition number which we assume as unity. that Ago takes the place of HO the difficulty ceases. NH,H HO SO = 44 NH,H Ago SO = 44 + NH,H = 66 NH,H,AgO CrO,= 44 + NH,H = 66 Perhaps the most anomalous salt in the whole series ex-amined is chloride of ammonium which actually decreases one volume in becoming solid 9 x 4 in solution being 11 x 3 in the state of a salt.Chloride of potassium refuses to share this anomaly and we accordingly find it 9.8 x 4 and NH,Cl associates itself to KC1 in the double salts. Four volumes for NH,C1 is undoubtedly what we should expect from its com-position and Trom that number being affected in solution and in its double salts. We also see the three volumes entering into alpha ammonia-chloride of copper although the beta ac-cording to our results seems singularly enough to affect the proper four volumes. NH,H H C l = 3 3 NH,Cu HC1= 33 + NH,H = 22 + HO = 11 = 66 NH,Cu HC1= 38.4 or 9% x 4 = 39*2 The double amides and chlorides as we have already shown, affect the same number of volumes as NH,Cl when in solu-tion and might be placed on the same type as NH,Hg HCl. Without denying that NH,H and HO may be so intimately associated in the ammoniacal salts as to form the hypothetical body oxide of ammonium we would call attention to the facts, which show that the resulting volumes of the ammoniacal salts are made up of the volumes of the hydrated acid and amide of hydrogen.It by no means militates against that view that in hydrated sulphate of ammonia w7e have one volume in solu-tion less and also in the state of a solid than should result from the combination of these two. CuCl has undoubtedly per se two volumes just as HC1 has in a concentrated state, or as NH,H has in combination. But the CuCl in CuCl + 2HO possesses only one volume the other having disap-peared in the water ; and HCl itself has only one volume in dilute solutions.The disappearance of one volume in combi-nation with water is by no means so surprising as the disap-pearance of the volumes of 23 atoms of the constituents of alum in the water in which it is dissolved especially when we find the salt under consideration sulphate of ammonia vindi-cating its proper volume when in combination. The oxalate of ammonia has its proper volume just as has anhydrous sul-phate of ammonia ; the only exception is the decidedly anoma-lous salt-chloride of ammonium although this also cease 416 Messrs. Playfair and Joule on to be anomalous in the double chlorides. By placing together the volumes of the hydrated acids and those of the ammoni-acal salts it will be seen that the latter are made up of the volumes of the hydrated acid united to amide of hydrogen affecting two volumes like HC1.Sulphate of ammonia= HO SO = 2 + NI3,H = 2 = 4 Nitrate of ammonia = HO NO =3 + NH,H = 2 =5 Oxalate of ammonia = HO C O,= 2 +NH,H =2=4 All the ammoniacal salts which we have described in this section may be arranged in a similar way with a like result. We do not profess to have resolved the cause of the equiva-lency HO + NH to KO; nor do we insist that they do not enter into more intimate union to form NH,O. It must not be left out of consideration however that in almost every in-stance the ammoniacal salt affects one volume in solution more than the corresponding salt of potash and that the number of volumes of the latter becomes augmented by one in pass-ing from the liquid to the solid state while the number of volumes of the ammoniacal salt remains unchanged.It re-quires a more minute knowledge of the constitutiori of salts than we now possess to decide the question at issue. Conclusion. Although we have examined many other salts than those described in the previous pages with results quite confirma-tory of our views we do not feel warranted in extending our 'memoir already much too long. We therefore conclude by summing up in the form of propositions the laws which we consider regulate the volumes of salts. At the same time we do so with strict reference to the salts which we have de-scribed deprecating their hasty generalization being our-selves quite satisfied that there are peculiarities in other cases, which must be subjected to close examination.This being only the first of several memoirs on the same subject which we intend to lay before the Society we do not present this investigation as being in itself complete. Prop. I.-Compounds dissolved in water increase its volume for every equivalent either by 9 or by multiples of 9. This in other words signifies that the volumes of salts in solxtion are either equal to each other or are multiples of each other; for 9 being the volume of nine grains or an equivalect of water is merely assumed as the standard of comparison. a. Certain salts snch as the magnesian sulphates th Atomic Volume and Spec;@ Gravity 477 alums &c. dissolve in water without increasing its bulk more than is due to the liquefaction of the water which they them-selves contain; the anhydrous salt taking up no space in so-lution.6. Anhydrous salts or salts containing a small proportion of water affect a certain number of volumes in solution which pass along with them unchanged into their union with other salts. c. The volume occupied by double salts when dissolved is the sum of volumes occupied by their constituents when separate with the exception of' certain cases described in the previous sections. Prop. 11.-The volume occupied by a salt in the solid state has a certaip relation to the volume of the same salt when in solution; and has also a $xed relation to the volume occupied by any other salt. a. The volume of an equivalent of any salt is either 11 or a multiple of 11 or of a number very nearly approaching the number 1 1.b. Or the volume of a salt is 9.8 or a multiple of 9.8 or, in other words of the volume occupied by an equivalent of solid water (ice). c. Or the volume of a salt is made up of a certain multiple of the number 11 added to a certain multiple of the number 9.8. On each of these heads we would offer a few remarks. With two assumptions we have been eiiabled to connect with each other the volrimes occupied by all the salts exa-mined by us in the previous sections. These assumptions are that the divisor for the volumes of salts is either 11 or a number very nearly approaching to it or that the divisor is 9.8 the volume of ibe itself. We have been guarded in stating positively that the first divisor is absolutely 11 because we do not in the present memoir enter into the connection between this number and the volume of ice 9.8.To show however that our experiments agree with those of recent accurate experimenters and that the number 11 which we have at present to announce empi-rically cannot be wide from the truth we append the theo-retical and experimental results upon the alums which we stated to possess twenty-five volumes in which therefore any considerable error in the number 11 would be multiplied by 25 and plainly show itself in the results. Notwithstanding this severe test it will be seen that the theoretical and ex-perimental numbers are actually within the errors of the balance 478 Messrs. Playfair and Joule on Theoretical. By Kppp's+ By our Mean of Potash alum. 1.721 ... 1.724 ... 1*?26 ... 1'725 Chrome alum 1.833 ...1.848 ... 1.826 ... 1.837 The number 11 must then be very near the truth if it be not absolutely the truth. We now append an equally severe test for our view that the volumes of many salts are multiples of 9'8 the number representing the volume of ice. If there be an error in this number it must become very notable in the phosphates and arseniates when multiplied by 24 or in carbonate of soda when multiplied by 10. Perhaps sugar itself will form as severe a test as could be desired for we pro-ceed on the extraordinary fact that the 12 atoms of carbon in sugar have ceased to occupy space and that the bulk of an atom of sugar is just the bulk of H, Oil or its 11 atoms of hydrogen and oxygen quasi water frozen into ice. sp. gr. experiments.experiments. experiments. Theoretical Sp. gr. ac- other ~~~~~- ities. sp. gr. cording to author-Carbonate of soda . 1.463 1-454 1*423 Haidinger. Phosphate of soda . 1-52? 1525 1.514 Tunnerman. Subphosphate of soda 1.622 1.622 none Arseniate of soda . 1.713 1.736 1.759 Thomson. Subarseniate of soda 1*808 1.804 none Cane-sugar . . . 1-591 1596 1.600 Schubler &Renz. Thus even in salts so difficult to obtain in a proper degree of hydration free from mechanical water as those given in the above table the difference between the theoretical and experi-mental numbers is not greater than might have been expected. We give one other class of salts to illustrate position c in Prop. II. there being in these salts a certain number of vo-lumes represented by 11 and a certain number by 9.8 CuO, SO representing the number of volumes with the divisor 11.Sulphate of copper . 2.270 2-254 2.274 Kopp. Theoretical Sp. gr. by our Sp. gr. by other sp. gr. experiments. authorities. .** zinc . . 1*926 1.931 1.912 Hassenfratz. ... iron . 1.854 1.857 1.840 Idem. ... magnesia 1'660 1-660 1.660 Idem. ... nickel . 2.033 ... 2*037 Kopp. We have selected these three classes of salts as being the most severe tests which we could apply to our theory and any chemist who has had experience in this subject mill at once admit that the theoretical and experimental numbers are * Anlralen de7 Pharmacie Ed xxxvi. S. 10 Atomic Volume and Spec.$c Gravity. 4 19 as near each other as the estimation of specific gravities by any two different experimenters We do not rest the claims of our theories on our own experiments but are willing to admit the accuracy of other experimenters especially of Karsten Hassenfratz Kopp and others who have preceded us on this subject*; while at the same time we believe that our methods of taking specific gravities have enabled us to introduce more uniformity into the results.The simplicity of the metho,ds themselves is due to Bishop Watson who was the first to take specific gravities by the increase in the stem of an instrumwt; and to Holker the suggestion is due of' using a saturated solution instead of the water employed by Watson. We conceive that the primitive volume 9.8 is transformable into the primitive volume 11 and vice versd and for this reason we sometimes see sulphate of ammonia 9.8 x 4 at other times, in combination as in bisulphate of ammonia or the anhydrous double sulphates, it is 11 x 4 ; and numerous other instances of transformation are presented in the previous sections.The liquid volume being to the solid volume either as 9 11 or as 9 9.8 these numbers used as the divisor for the liquid and solid volumes respectively usually yield the same quotient. Thus the liquid volume of stdphate of cop-45 55 per is 45 its solid volume is 55. - = 5 and - = 5 ; 9 11 so that we say the salt affects the same number of volumes in the liquid and in the solid state. I n the same manner subphosphate of soda has a volume of 216 in solution and of 235 235 in the state of salt. Now E6 = 24 and - = 24 so 9 9.8 that the number of volumes affected in solution and in the solid state are exactly the same.This is a general rule and a powerful argument ofthe accuracy of our position. The rule has exceptions in salts of potash in which the volumes are increased by one volume on becoming solid; thus KO SO, = -= 2 in solution and - = 3 in the solid state. This is * The only decided difference which we found from other experimenters is in the case of hydrated salts. Thus our determination of the voluiiies of the double magnesian sulphates and sulphate of potash (Table VI.) djf-fers from Kopp's experiments as 99 103. These salts contain fioni 3 to 4 per cent. of mechanical water as Graham Iong ago pointed out (Trans. R. S. E. vol. xiii. p. IZ) and the neglect of this in Kopp's experiments has probably caused the difference.We take this opportunity of stating that when more than one specific gravity is given by us the salts have been prepared at different times j in many instances this is not the case but in much the largest proportion it is so. 18 33 9 1 480 Messrs. Playfair and Joule on not an accidental variation but an actual augmentation of one volume as is proved by the potash alums in which KO SO, has ceased to occupy space in solution but on the crystalliza-tion of the alum the volume becomes increased by one ob-viously owing to this peculiarity of KO SO,; thus alum in solution - = 24 becomes -25 in the state of a salt. 216 275 -9 11 This peculiarity is very striking especially in the case KO CO, which with a volume of - = 3 as a solid be-comes -= 1 as a liquid. Let us endeavour to conceive the extraordinary amount of power exerted in this case ; the water in the volumenometer on dissolving an equivalent of KO CO,, descends from 33 to 9 so that a bulk of solid matter = 24 grains of water disappears within it. If we would compare the force to that which would be required to compress the water into this diminished bulk we must deal in numbers of a magni-tude truly immense. We have always been accustomed to view as an exception the expansion of water on becoming solid but now we see with Longchamp that the rule is universal; the salt (muriate of ammonia excepted?) takes up more space as a solid than it does in its liquid state in solution. We have stated that we desire not to be held responsible for any rash generalization of these laws which we do not extend at present beyond the salts examined by us. Let us con-sider the volumes of the ammonia alums as an example of the danger of applying either of the laws without a proper comprehension of them. These volumes are certainly above 275 the volumes of the potash alums and are between 279 and 280 according to our experiments and those of Kopp. Now let .us suppose that the four volunies of NH,O SO are represented in the alums and that only Al,03 3S0 has ceased to occupy space as it in fact does when hydrated, then an ammonia alum A1,0, 3S0 + NH,O SO + 24HO may be viewed as 9*8 x (24 + 4) = 279*4 and the specific gravities would .countenance this idea. Sp. gr. by our Sp. gr. by Kopp’ 33 11 9 9 Sp. gr. by Theory. experiments. experiment. Ammonia alum . . 1.626 1*625 1.626 Ammonia iron alum 1*721 l*?lS 1.712 These results certainly approach the theoretical number very closely; and the theory may represent the truth. But at the same time it is difficult to believe that the ammonia alum is constituted on a different type from the potash alum. We might suppose that the only variation between them is th Atomic Volume and Spec@ Gravity. 451 difference between the volumes of KO SO and NH,O SO, or the difference between 11 x 3 and 9% x 4. This cliffer-ence 6.2 added to the volume of potash alum 275 + 6.2 = 281.2 which is not very wide from the experimental results, and would give the specific gravity by theory for ammonia alum 1.616 and for ammonia iron alum 1.711. These are points which require further inquiry. We do not refer here to the minor views embraced in the preceding investigation being anxious principally for inquiry and confirmation into the three main theories propounded. With one assumption for the volume in solution and with two assumptions for the volumes of solids we have been enabled to explain as we trust the specific gravities detailed in the previous sections. We might perhaps with propriety indulge in speculation and apply these laws in explanation of iso-morphism and dimorphism but we prefer the safer course of trusting to experimental investigation part of which we shall in a short time lay before the Society in an inquiry upon the expansion of solutions and on some other points connected with this important subject

ISSN:0094-2405    

DOI:10.1039/MP8430200401

出版商:RSC    

年代:1843

数据来源: RSC

摘要:

ERRATA. Page 12,forCsN,H40S=C8N2H30t+H0 readCsN2H O9=CsN2H4Os+HO. - 228 f o r chlorisat n and bichlorisatin read chlorisatine and bichlorisatme. - 228 229 234,243 251,252 253 254 f o r anilene read aniline. - 269 for phenyl read phenyle

ISSN:0094-2405    

DOI:10.1039/MP8430200482

出版商:RSC    

年代:1843

数据来源: RSC

摘要:

I N D E X . __f_ ACIDS :-meconic 1 114 ; kome-nic 1 7 117 ; pyromeconic 2 ; py-romucic 5 ; pyrokomenic and para-komenic 6 ; uric 9 ; dialuric 1 1 ; acid thionurate of ammonia 13 ; alloxano-sulphurous ib. ; alloxanic, 14 ; ferric 25 7 catechuic 45 ; neu-tralization of various by hydrate of potash 51 ; of hydrate of potash by nitric sulphuric and hydrochloric, 52,58 ; ofacetic oxalic arsenic and phosphoric by hydrate of potash 65, 63; action of upon spathic carbonate of iron 106 ; on some salts of meconic and komenic 113 ; iron salt from zthereal solution'of meconic 116 ; on separating lime and magnesia when they exist in cornhination with phosphoric 140 ; opianic 173 ; he-mipinic 172 ; on sulphuric phos-phoric and carbonic in vegetable ashes 182 189 190 ; acids in Bon-ningtoii water 207 ; in bones from guano 225 ; kinic 226 ; action of nitric on chloraniline and on sty-role 283,339 ; benzoic 312 ; nitro-benzoic 343 ; action of chromic and sulphuric on styrole and of nitric, on metastyrole 344 345 351 ; phosphoric in the deep-well water of the London basin 392.Actino-chemistry contributions to, 311. athogen 15. Alaria esculenta mannite contained in 138. Alkalies in vegetable ash 188 190. Alkaline earths in vegetable ash 287. Alloxanic acid 14. Alloxano-sulphurous acid 13. Alloxantitie 10. Alloy of zinc iron lead and copper, Alums volumes of certain 414. American guano composition of some varieties of South 140 ; analysis of samples 149 150. Ammonia komrnate of 8 ; djalurate of 11 ; acid thionurate of; 13; on a crystallized 393.komenate of 118; new mode of estimating 140 ; in the Bonnington water 215 ; decomposition ot' salts of 244. Analyses :-pyromeconic acid 2 ; pa-rakomenic acid 7 ; komenate of peroxide of iron 8 ; catechu and cutch 47; of a silver vase found between Bow and Stratford 48; double sulphates 50 ; of recent and fossil bones 98 ; spathic carbonate of iron 105; meconic acid 113 ; meconate of lead 114; komenate of ammonia lead copper and silver, 118 119 120; hydrate of the oil of turpentine 121 ; East Indian grass oil 123 ; Laminaria saccha-rina 137 ; South American guano, 149; concrete guano 151 ; saline guano 152 ; narcotine 163 ; vege-table ashes abounding in silica 190; ashes of tobacco wheat rye peas, the apple-tree 192 2.93; of seed-ashes containing tribasic and biba-sic phosphates 195 197; diseased wheat 199; of the Bonnington water and the soluble and earthy ingredients in the 201 206 211 ; carbonic acid gas and ammonia, 215 ; of bones from the guano 225 ; chloranil 230 ; green glass 248 ; hydrochlorate of chloraniline 280 ; farm-yard manure and coal-gas, 309; brown iron ore 322 321, 325 ; hydrochlorate of toluidine, 379 ; of gingerade 386; of zinc plates 394.Andropogon Iuaracusa oil of the 122. Aniline on the formation of 249; action of chlorine on 270. Anniversary Report and Address 109, 329. Antimony solubility of 20. .4pple-tree analysis of the ash of 193. Arrott (A. R.) on a class of double sulphates containing soda and a magnesian oxide 49.Arseniates volumes occupied by 41 8. Arsenic solubility of 20 ; improve 484 INDEX. method for the detection and quan-titative determination of 129; de-coloration and solution of substances by 130; separation of the as sul-phuret of ib.; purification of sul-phuret of 131 ; quantitative deter-mination of the sulphuret of ib.; reduction of the sulphuret of 132. Ash-analysis method of quantitative, 184. Ashes vegetable inorganic com-pounds in the normal 182; rich in alkaline and earthy carbonates 183, 186; in alkaline and earthy phos-phates 184 186; in silica 164, 190 ; preparation of the 184 ; car-bonic acid in 190. Ashes of tobacco analysis of the 192. Atomic volume 011 401. Auditors’ Report 112 333. Balinain (W.H.) on sethogen 15. Baryta action of anhydrous and lime, Benzoic acid 342. Bicarbonate of potash neutralization of with hydrate of potash 68. Uichlaride of platinum products of decomposition of narcotine by 163, 16s. Bichromate of potash neutralization of by hydrate of potash 64. Binosalate of potash 66. Bismuth solubility of 20. Bleaching powder action of on the salts of’ copper and lead 387. Blyth (Dr. J.) on the composition of narcotine and some of its products of decomposition by the action of bichloride of platinum 163; on styrole and some of tlie products of its decomposition 334. Bones occurrence of fluorine in recent as well as in fossil 97 134; curious change in the composition of taken from the guano 223. Bonnington water analysis of the 201.Bromaniline composition of 290 ; properties of 291 ; osalate of ib. ; hydrochlorate of 292 ; bichloride of platinum 293. Bromides 440 ; volumes in solution and in the solid state of certain 416. Bromine in the Bonnington water, 209 ; production of organic bases which contain 266 ; action of 011 chIoraniline 283 ; on styrole 345. Hromisntine action of fused hydrate on chloraniline 284. of potash on 289; compounds of, 291. Bromostyrole 345. Bunsen (Prof.) on the direct forma-tion of cyanogen from the union of the nitrogen of the air with carbori, 391. Burnard (C. F.) on a modification of the apparatus for estimating the carbonic acid in carbonated alka-lies &c. 199. Cadmium solubility of 19. Calamus aromaticus oil of the 122.Cnne-sugar on the conversion of 38.1 ; volumes occupied by 428. Carbonate of iron spathic 105. Carbonates vegetable ashes rich in alkaline and earthy 183 ; analysis of 186 ; atomic volume of 453 ; volumes occupied by the alkaline, 454. Carbonic acid in vegetable ash 190 ; on the apparatus for estimating the, in carbonated alkalies &c. 199. Carty (John) on a new cyanide of gold 80 ; on a specimen of diseased wheat 199. Catechu analysis of 47. Catechuic acid 45. Cellulose and inulin on the conver-sion of cane-sugar iuto a substance isomeric with 384. Cerealis oxide of copper in 183. Charcoal determination of the silica of the in vegetable ash 186; ac-tion of animal 326. Chemical combination actinic influ-elice on 317.Chemical lamp-fiiniace on a 218. Chinolin and leucol identical 384. Chloranil 227. Chloraniline 273 ; properties of 2’74 ; compounds of 276; sulphate of, 277 ; binoxalate of 278; phosphate of 280 ; hydrochlorate of ib. ; pro-ducts of the decoinposition of 281 ; action of the oxygenated compounds of chlorine on ib. ; action of chlo-rine on 283; of bromine on ib.; .of nitric acid on ib.; of anhydrous baryta and lime on 284 ; of potas-sium on 285. Chlorides 440 ; volumes in solution and in the solid state of certain, 446 447. Cblorindatmit on the tnic composi-tion of 306 INDEX. 485 Chlorine in vegetable ash 189 ; in the Bonnington water 208 ; decompo-sition of oxides and salts by 234 ; production of organic bases which contain 266 ; action of on aniline, 270 ; of the oxygenated compounds of on chloraniline 281 ; action of on chloraniline 283 ; on styrole 346.Chlorisatine action of fused hydrate of potash on 272. Chloro-carbon oxalate of 365. Chlorodibromaniline 288. Chlorostyrole 346. Chromates 448 ; volumes occupied by certain 450. Chromic acid action of 011 styrole, 344. Cinnamole 353, Clark (Dr.) on the removal of lead, the chief poison to he apprehended in water by an effective filter, 384. Coal-gas analysis of 309. Cobalt solubility of 20. Compounds conjugate 360. Cooper (John Thomas) on catechuic acid 45. Copper pyromeconate of 3 ; kome-nate of 119; discovery of pure oxide of nickel in the scum arising from smelting of 384; action of bleaching powder on the salts ‘ of, 387.Cotarnin formation of hydrochlorate of 171. Couch grass supposed existence of mannite in the roots of 139. Crum (Walter) on the action of bleach-ing powder on the salts of copper and lead 387. Cutch analysis of 47. Cyanide of gold 80 82 86 ; of pot-assium 82 92; of gold and pot-assium 88 ; of silver 98 ; decompo-sition of the double by an electric current 158. Dauben? (Dr. Charles) on the occur-rence of fluorine in recent as well as in fossil bones 97. De la Rue (W.) on the structure of electro-precipitated metals 300 ; on a crystallized alloy of ziuc iron, lead and copper 393. Dialurate of ammonia 11. Dialuric acid 11. Dibromaniline composition of; 29 1 ; properties of 2%. Dibromisatine action of fused hydrate of potash on 294.Dichloraniline 285. Dichlorisatiue action of the fused hydrate of potash on 285. Draconyl 357. Drayton’s (Mr.) new method of cover-ing glass by precipitation with a coating of metallic silver 128. Earths alkaline in vegetable ash, 187. East Indian grass oil on 122. Electric curreri t decomposition of the double cyanides by an 158 ; on the deconiposition of metallic salts by an 255. Electro-chemical action actinic influ-ence on 319. Electro-precipitated metals on the structure of 300. Fermentation observations on 21. Ferric acid on 25. Fluids on the circular polarization of light by transmission through 26. Fluoride of iodine preparation of 162. Fluorine occurrence of in recent as well as in fossil bones 97 ; and the sources from whence it is derived, 134.Fresenius (Dr. Remigius) on an im-proved method for the detection and quantitative determination of arsenic 129 ; on the inorganic con-stituents of plants 179. Fucus vesiculosus F. serratus and F. nudosus mannite contained in 138, 139. Furnace on a chemical lamp 218. Furze (John N.) on fermentation 21. Gas carbonic acid amount contained Gas-lime composition of 359. Genth (M.) on the discovery of pure oxide of nickel in the scum arising from smelting of copper 384. in the Bonnington water 215. Gingerade analysis of 386. Glassford (Charles F. 0.) on the cy-anides of the metals and their com-binations with cyanide of potassiuin : -Part 1. Cyanide of gold 82; Part 11. Cyanide of silver 92.Glass on some commercial specimens of green 247. Gold solubility of 20; cyanide of, 80 82 86. Graham (Thomas) on the heat disen-gaged in combinations 51 ; on th 486 INDEX. useful applications of the refuse-lime of gas-works 358 ; on the existence of phosphoric acid in the deep-well water of the London basin 392. Grass oil East Indian 122. Gravity on specific 401. Gregory (Dr.) on the chemical history of the products of the decomposi-tion of uric acid 9 ; on a new phos-phate of magnesia 310. Guano coniposition of some varieties of South American 140; analysis of samples of 149 150; of con-crete 151 152; of saline ib.; on bones taken from the 223. Halydris siliquosa mannite contained in 138. Hemipinic acid 172. Hodges (Dr. J.F.) on the pharma-ceutical and chemical characters of the Peruvian matico 123. Hofmann (A. W.) on chloranil 227 ; on certain processes in which ani-line is formed 249; on the meta-m~rphoses of indigo-production of organic bases which contain chlo-rine and bromine 266 ; on the true coinposition of chlorindatmit 306 ; nn styrole and some of the pro-ducts of its decomposition 334 ; on toluidine a new organic base 367 ; lericol and chinolin identical 384. Hunt (R.) on actino-chemistry 31 1. Hydrate.of the oil of laurel turpen-Indigo metamorphoses of 266. Inulin on the conversion of cane-sugar into a substance isomeric with cel-lulose and 384. Iodides 440 ; volumes in solution and in the solid state of certain 447. Iodine preparation of fluoride of 162; in the Bonnington water 208.Iron pyromeconate of 4 ; komenate of peroxide of 8 ; on the solubility of the metals in persulphate and per-chloride of 16; spathic carbonate of, 105 ; meconic acid and the persalts of J14; reduction of the salts of peroxide of by means of vegetable substances 120 ; peroxide of in ve-getable ash 187 ; oside of contain-ed in the Bonnington water 218. Iron ore on brown 32 1 ; coinposition and quantitative analysis of 322. Iron salt from Ethereal solution of meconic acid 116. tine 121. Isatine action of hydrate of potash in fusion on 271. Jones (Dr. H. Bence) on the decom-position of salts of ammonia at or-dinary temperatures 244. Joule (J. P.) on atomic volume and specific gravity 401. Kinic acid on detecting 226.Kolbe (Dr. H.) on conjugate com-pounds 360. Koinenate of peroxide of iron 8 ; of ammonia 8 118 ; of lead ib.; of copper 119 ; of silver 120. Komenic acid products of the distilla-tion of 6 ; preparation of salts of, 113 117. Laminaria saccharina and other sea-weeds occurreiice of mannite in the, 136 138. Lead solubility of 19 ; meconate of, 113; komenate of 118; action of bleaching powder on the salts of, 387 ; solubility of oxide of in pure water 399. Leeson (Dr. H. B.) on the circular polarization of light by transmission through fluids 26 ; on the prepara-tion of fluoride of iodine 162. Leucol and chinolin identical 384. Light on the circular polarization of, by transmission through fluids 26. Lime process of separating the phos-phate of from magnesia 142; 011 a new hydrated phosphate of 222 ; action of anhydrous baryta and on chloraniline 284 ; useful applica-tion of the refuse of gas-works, 35s ; composition of gas 359.Liquids table of some rotating 44, 45. London basin existence of phosphoric acid in the deep-well water of the, 392. Maclagan (Dr. Douglas) on the con-version of cane-sugar into a sub-stance isomeric with cellulose and inulin 384. Magnesia on separating the phos-phate of lime from 142 ; on a new phosphate of 310. Mannite occurrence of in the Lami-naria saccharina and other sea-weeds 136 ; supposed existence of, in Triticitm rcpens or couch grass, 139. Manure analyses of farni-yard 309. Matico Peruvian on the pharmaceu INDEX.487 tical and chemical characters of the, 123. Meconate of lead 113. Meconic acid products of the distil-lation of l 6 ; salts of 113; and the persalts of iron 114; iron salt from aethereal solution of 11 6. Mercury bichloride of and chlorani-line 281. Metals solubility of the 16 ; cya-nides of the and their combinations with cyanide of potassLum 82 92 ; on the structure of electro-preci-pitdted 300. Metastyrole 347. Methyl hyposulphate of 364. Microscope on preserving salts for the 71. Middleton (J.) on fluorine in recent and fossil bones and the sources from whence it is derived 134. Murray (R.) on the phsenomena of sounds produced in a bar of soft iron 201. Muspratt (J. S.) on certain processes in which aniline is formed 249 ; 011 toluidine a new organic base, 367.Napier (James) on the solubility of the metals in persulphate and per-chloride of iron 16; on the cya-nides of the metals and their com-binations with cyanide of potassium: -Part I. Cyanide of gold 82 ; Part PI. Cyanide of silver 92; on the decomposition of the double cya-nides by an electric current 158 ; on the decomposition of metallic salts by an electric current 255. Narcogenin 173. Narcotine atomic weight of 163 ; composition of 163 165 ; products of decomposition 168 177. Nickel solubility of 20 ; discovery of pure oxide of in the scum arising from smelting of copper 384., Nitraniline 382. Nitrates 435 ; volumes occupied by certain 440. Nitric acid action of on chloraniline, 283 ; on styrole 339 ; on metasty-role 351.Nitrobenzoic acid 343. Nitrometastyrole 351. Nitrostyrole preparation of 339. Officers and Council in 1844,113 ; in 1845,334. Chem. Xoc. Mem. VOL. XI. Oils essential possessing no rota-ting energy 49 ; hydrate of the of laurel turpentine 121 ; East Indian grass 122. Opianic acid 172. Ore on brown iron 321; composi-tion and quantitative analysis 322. Oxide on a class of double sulphates containing a magnesian 49, Oxides decomposition of by chlorine, 234. Ozone 395. Parakomenic acid 6. Peas analysis of the ash of 193. Percy (Dr. John) on a new hydrated phosphate of lime 222. Peruvian matico on the pharmaceu-tical and chemical characters of the, 123. Pharmacopias on the distilled waters of our 261. Phosphates vegetable ashes rich in alkaline and earthy 184 ; analysis of 186 ; analysis of seed-ashes con-taining tribasic and bibasic 195, 196; volumes occupied by 418.Phosphoric acid in vegetable ash 189. Plants inorganic constituents of 179 ; determination of the quantity of ve-getable ash in 190. Platinum products of decomposition of narcotine by bichloride of 163, 168; bichloride of and chlorani-line 280 ; bromaniline and bichlo-ride of 293. Playfair (Lyon) on atomic volume and specific gravity 401. Potash neutralization of various acids by hydrate of 51 ; of hydrate of, by nitric and hydrochloric acids, 52; of hydrate of by eiilphuric acid 58 ; of bichromate of by hy-drate of 64 ; of acetic acid by hy-drate of 65 ; of oxalic acid ib.; binoxalate of 66 ; quadroxalate of, 67 ; neutralization of bicarbonate of, with hydrate of 68 ; of arsenic and phosphoric acids by hydrate of ib.; action of hydrate of in fiision on isatin 271; of fuied on chlorisa-tine 272 ; on dichlorisatine 285 ; on bromisatine 289 ; on dibromisa-tine 294 ; influence of solar rays on manganate of 313. Potassa in the Bonnington water 209. Potassium on the cyanides of the me-tals and their combination with 2 488 INDEX. cyanide of 82,92 ; cyanide of gold and 88 ; action of on chloraniline, 285. Precipitates colour of when exposed to solar rays 316. Precipitation influence of the solar rays on 31 2. Pyrokomenic acid 6. Pyromeconate of copper 3 of iron 4. Pyromeconic acid 2 5. Pyromucic acid 5.Quadroxalate of potash 67. Report Auditors’ 112 333. Rhodomenia palmata mannite con-tained in 138. Richardson (Thomas) analyses of farmyard manure and of coal-gas, 309. Rye analysis of the ash of 193. Salts,on a means ofpreserving the cry-stals of as permanent objects for microscopic investigation 71 ; iron, from athereal sohition of meconic acid 116; reduction of the of per-oxide of iron by means of vegetable substances 120 ; decomposition of, by chlorine 234 ; decomposition of, of ammonia 244 ; decomposition of metallic by an electric current 255; volumes occupied by certain con-taining a large amount of hydrate water 412; volume occupied by certain hydrated rendered anhy-drous 433 ; ammoniacal 460 ; vo-lumes occupied by 466 ; lams which regulate the volumes of 476.Sand determination of the silica of the in vegetable ash 186. Schweitzer (G.) on an analysis of the Bonnington water near Leith Scot-land 201. Sea-weeds occurrence of mannite in, 136. Seed-ashes analyses of‘ contairiing tri-basic and bibasic phosphates 195, 196 197. Silica vegetable ashes rich in 184, 186 190. Silver curious change in the moIecn-lar structure of 47 ; cyanide of 92 ; komenate of 120 ; new method of covering glass by precipitation, with a coating of metallic 128 ; on some of the substances which reduce oxide of 242. Smith (J. Denham) on ferric acid 25 ; on the composition of some varieties of South American guano; with the description of a new mode of esti-mating ammonia and of a process for separating lime from magnesia, when these earths exist in combi-nation with phosphoric acid 140.Soda on a class of double sulphates containing 49; in the Bonnington water 210 ; volumes occupied by carbonate of 418. Solar rays influence of the on preci-pitation 312. Solly (Edward) on a chemical lamp-furnace 218. Stenhouse (Dr. John) on the products of the distillation of meconic acid, 1 ; on some of the salts of meconic and komenic acid 113 ; on the re-duction of the salts of peroxide of iron by means of vegetable sub-stances 120 ; on the hydrate of the oil of laurel turpentine 121; on East Indian grass oil 122 ; on the occurrence of mannite iii the Lanai-naria saccharina and other sea-weeds 136; on a means of detect-ing kinic acid 226 ; on some of the substances which reduce oxide of silver and precipitate it on glass in the form of a metallic mirror, 242.Styrole 334 353 ; preparation of, 336 ; properties of 337 ; composi-tion of 338; products of the de-composition of-action ofnitric acid7 339; action of chromfc acid on 344; of fuming sulphuric acid on 345 ; of bromine on 345 ; of chlorine on, 346 ; of heat on 347. Subsalts examination of,460 ; volumes occupied by 466. Sulphates on a class of double con-taining soda and a magnesian oxide, 49; volumes of certain anhydrous and double 422 427. Sulphuric acid in vegetable ash 189. Teas green of commerce 73. Tilley (Thomas) on the conversion of cane-sugar into a substance isomeric with cellulose and inulin 384. Tin solubility of 19.Tobacco analysis of the ashes of 192. Toluidine 367 ; Preparation of 373 ; composition of 375 ; properties of, ib.; compounds of 377; sulphate of 378; binoxalate of ib. ; hydfo-chlorate of 379 ; platinchloride of INDEX. 489 ib. ; products of the decomposition of 380. Toluol preparation of 371. Tribromaniline 296. Trichloraniline 286. Triticum repens or couch grass sup-posed existence of mannite in the roots of 139. Turpentine hydrate of the oil af lau-rel 122. Uric acid on the chemical history of the products of the decomposition of 9. Veptable substances on the reduc-tion of the salts of peroxide of iron by means of 120. Vegetables inorganic compounds in the ashes of 182. Warington (Robert) on a curious change in the molecular structure of silver 47; on a means of pre-serving the crystals of salts as per-manent objects for microscopic in-vestigation 71 ; on the green teas of commerce 73 ; on Mr.Drayton’s new method of covering glass by precipitation with a coating of me-tallic silver 128; on a curious change in the composition of bones taken from the guano 223; on some comiiiercial specimens of green glass 247 ; on the distilled waters of our pharmacopaeias 261 ; on the a s tion of animal charcoal 326. Water Bonnington analysis of the, 201; quantitative analysis of the soluble and earthy ingredients in, 206 211 ; existence of phosphoric acid in the deep-well of the Lon-don basin 392 ; solubility of oxide of lead in pure 399 ; volumes oc-cupied by certain salts containing a layge amount of hydrate 412; sulphates with a small proportion of hydrate 427. Waters on the distilled of our phar-macopceias 261. Way (John Thomas) on a spathic car-bonate of iron 105. Wheat analysis of the ash of 193; on a specimen of diseased 199. Will (Dr. H.) on the inorganic con-stituents of plants 179. Williamson (Alexander W.) on the decomposition of oxides and salts by chlorine 234 ; on ozone 395. Yorke (Lieut.-Col. P. I.) on brown iron ore 321; on the solubility of oxide of lead in pure water 399. END O F VOL. 11. Printed by Richard and John E. Taylor Red Lion Court Fleet Street

ISSN:0094-2405    

DOI:10.1039/MP8430200483

出版商:RSC    

年代:1843

数据来源: RSC