336 CONTRIBUTION TO STUDY OF HYDROXYLAMINE.— MACKAY. 



By judiciously controlling the degree of overwarining, the 

 overcooling could be kept within 1/10 of a degree. As the 

 overcooling seldom exceeded this, it was not considered neces- 

 sary to make any correction for change in concentration, as the 

 degree of accuracy otherwise attained would not justify it. 



The solutions used were made up according to volume at 

 18° C, and the molecular depresssion calculated according to 

 Arrhenius. The water used was the same as that used for the 

 conductivity measurements, and the freezing point was deter- 

 mined each day in order to eliminate errors due to variation in 

 the barometer. 



The following results were obtained 



Grams of NH2OH used per 

 liter of solution. 



Number of liters 

 per gram molecule. 



1. 



2 



5 



10 



20 



50 



100 



500 



Depression of 

 freezing point 



7746. 

 8900. 

 3607. 

 1808. 

 0950. 

 0391. 

 0204. 

 0045 . 



Molecular 

 depression. 



77 

 78 

 80 

 81 

 90 

 96 

 04 

 25 



These results are in general agreement with the conductivity 

 measurements, at corresponding dilution, in showing the slight 

 dissociation of hydroxy la mine solutions. 



For the sake of comparison, it may be of interest to give the 

 values of the molecular d pression by ammonia in aqueous solu- 

 tion as found by Jones^, and also the specific equivalent conduct- 

 ivities for annnonia, and potassium hydi'oxide, taken from 

 Whetham's^ tables. 



1. Zeitschr. phys. Chem., 12, 623, (1893). 



2. Theory of Solution, 1902. 



