434 REPORTS ON THE STATE OP SCIENCE. 



absorption of carbon dioxide in water does not take place in accordance 

 with Dalton's law. 



He pointed out that in this case chemical action probably takes place 

 between solute and solvent. 



Determinations of the solubility of carbon dioxide in carbon 

 bisulphide at various temperatures show an approximation to Dalton's 

 law. He published later IS0 the results of determinations made in 

 chloroform. 



1892 An im P 01 ' tant paper by Elard 1SG furnished an interesting 



comparison of the behaviour of mercuric and cupric chlorides in 

 various organic solvents; the solubility results were plotted as functions 

 of temperature; the observations ranged from -60° to +210°. The 

 solvents employed were water, methylic alcohol, ethylic alcohol, propylic 

 alcohol, iso-butylic alcohol, acetone, acetic acid, ethylic acetate, ether, 

 and ethylic formate. 



Great similarity was observed in all parts of the graphs representing 

 the results obtained with water, methylic and ethylic alcohols, the 

 graphs for u-propylic alcohol and iso-butylic alcohol only being similar 

 to the foregoing alcohols in the region representing temperatures 

 above 40°. 



With the exception of ether, ethylic formate, and ethylic acetate, all 

 the graphs show distinct points of flexure when mercuric chloride is the 

 solute, but with cupric chloride the graphs appear as straight lines. 



Lobry de Bruyn 199 found that with hydrated magnesium sulphate 

 and zinc sulphate, methylic alcohol as a solvent lies between water and 

 ethylic alcohol. Similar results to this were found by DeUpine 191 in 

 the case where ammonia was the solute, the coefficient of solubility 

 at 0° being for ethylic alcohol 201), for methylic alcohol 425, and for 

 water SO'J.- 



Mention must be made of Steiner's 219 work on the solubility 

 of hydrogen in aqueous sugar and salt solutions. It is significant 

 that the salts giving greatest molecular effect in the more dilute solutions 

 are sodium sulphate, magnesium sulphate, calcium chloride, aluminium 

 chloride, and potassium carbonate, all of which decrease rapidly in 

 action as their concentration is increased. Salts which produce smaller 

 molecular lowering of the solubility coefficient of hydrogen are sodium 

 chloride, potassium nitrate, potassium chloride, lithium chloride, 

 sodium nitrate, and also cane sugar; all these decrease but slightly as 

 their concentration is increased. 



IV. A. — Nature of the Solute — Physical. 



Like his attempts to establish some relationship between the solu- 

 bility of a substance and its nature with the nature of the solute (vide 

 1fi _. Section III. B), Kremers' endeavours to trace a connection 

 ' between the atomic volume of the solute and its solubility were 

 unsuccessful. 



.^2 1'ou Hauer 44 considered the study of solubility afforded a 



means of determining the isomorphous nature of salts with con- 

 siderable accuracy. 



* This value is given by Sims, Ann. d. Pharm., 118, 345. 



