Prof. Graham on the Diffusion of Liquids. 271 



proportions of salt. It is possibly a consequence of the cry- 

 stallizing attraction, to which reference was lately made, coming 

 into action in strong solutions and resisting diffusion 



(6.) The diffusion of chlorate of potash was observed at a 

 temperature ranging from 63° to 65°, of which the mean was 

 64°-l. 



Table XII.— Diffusion of Chlorate of Potash. 



Parts of salt to 100 water. 



Density of solu- 

 tion at 60°. 



At 64°-l 



Experiments. 



Mean. 



2 

 4 



6*5 (saturated solution). 



10129 

 10246 

 10395 



6-97 

 754 

 716 

 1303 

 13-64 

 1327 

 21-30 

 20-29 

 20-76 



7-22 

 13-31 



20-78 



The solutions of chlorate of potash must be evaporated and 

 the residuary salt dried at a temperature not exceeding 212°, 

 otherwise a very sensible quantity of chloride of potassium 

 may be formed. The chlorate appears to be sensibly inferior 

 in diffusibility to the nitrate of potash. From the 4 per cent, 

 solution of the chlorate we have a diffusion product of 13-27 

 grs., and from the corresponding solution of the nitrate 13*97 

 grs. ; but the latter was obtained at a temperature 1°*8 higher 

 than the former. It remains a question whether chlorate of 

 potash does not really belong to the nitre group of salts, but 

 has its diffusion interfered with by some secondary agency, 

 such as its sparing solubility and consequent nearer approach 

 to the saturating proportion. 



It is certainly true that the uniformity of diffusion generally 

 increases with the dilution of the solutions. This appears on 

 comparing the diffusion of the 4 per cent, solution of what 

 may be called the sulphate of potash group, with the diffusions 

 of the 2 per cent, solutions of the same salts. 



Diffusion of Salts of the Sulphate of Potash Class. 





4. 



2. 



Carbonate of potash 



10-27 

 10-57 

 10-51 

 10-70 

 11-01 

 11-19 

 11-49 



5-45 

 5-52 

 5-58 

 5-85 

 5-81 

 5-77 

 5-65 



Sulphate of potash 



Sulphate of ammonia 



Acetate of potash 



Bicarbonate of potash 



Chromate of potash , 



Bichromate of potash 



