Bromine, solubility, salt soln

The general effect of the presence of a salt in soln. is to reduce the solubility of bromine,30 and this the more the greater the cone, of the salt. For example, with a j-yV-soln. of sodium nitrate, 3 374 grms. of bromine were dissolved per 100 c.c., and with a iV-soln., 2 88 grms., while the solubility of bromine in water at 25° is 3-395 grms. per 100 c.c. The effect of a few typical salts, in grms. per 100 c.c., on the solubility of bromine—grams per 100 c.c.—in water is as follows ... 

The increase in the solubility of bromine in soln. of ammonium salts is very marked, as is also the case with the alkali chlorides. The case with the alkali bromides is specially interesting. The solubilities by F. P. Worley are indicated in Table IX. The marked increase in the solubility of bromine in soln. of potassium bromide was attributed by M. Roloff to the formation of molecules of KBr3. He shook up a soln. of bromine in carbon disulphide with water and with an aq. soln. of potassium biomide, and measured the concentration of the bromine in the two layers. M. Wildermann has shown that the density of bromine vapour over a soln. of potassium bromide sat. with bromine is the same as over water sat. with bromine, indicating that the cone, of the free bromine in all the aq. soln. is the same, and any excess in the presence of potassium bromide must be united with the potassium bromide. All the bromine dissolved by a soln. of potassium bromide can be removed... 

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