114 Van Name and Huff- — Hydrolysis and Electrical 



dilutions of 32, 64, 128, etc. liters, upon the assumption 

 (sufficiently accurate for the short intervals involved), 

 that the conductivity is a linear function of the logarithm 

 of the dilution. The results are given in Table V, and 



Table V. 



Molecular Conductivity of Hypophosphoric Acid at 25°. 

 Referred to Formula H 4 P 2 0,j. 



After complete hydrolysis. 





v- 



V- 



m 



^ 



m 



i" 



Dilution 



Sol. A 



Sol. B 



Mean 



Sol. A 



Sol. B 



Mean 



lit./mol. 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



32 



382-3 



387-2 



384-7 



347-2 



347-6 



347-4 



64 



416-8 



421-2 



419-0 



415-2 



414-3 



414-7 



128 



458-2 



460-9 



459-5 



486-2 



485-3 



485-8 



256 



508-2 



5110 



509-6 



5570 



557-6 



557-3 



512 



567-7 



5710 



569-3 



616-4 



621-2 



618-8 



1024 



6261 



632-6 



629-3 



6680 



6850 



676-5 







Referred 



to Formula H,P0 3 . 















After 



complete hydrolysis. 



A , . 





^ 



fj- 



/* 



M 



M 



^ 



Dilution 



Sol. A 



Sol. B 



Mean 



Sol. A 



Sol. B 



Mean 



lit./mol. 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



ohm- 1 



16 



1911 



193-6 



192-3 



173-6 



173-8 



173-7 



32 



208-4 



210-6 



209-5 



207-6 



207-1 



207-4 



64 



2291 



230-4 



229-7 



2431 



242-6 



242-9 



128 



2541 



255-5 



254-8 



278-5 



278-8 



278-6 



256 



283-8 



285-5 



284-6 



308-2 



310-6 



309-4 



512 



3130 



316-3 



314-6 



3340 



342-5 



338-2 



for convenience are expressed also in terms of the 

 simpler molecular formula, H 2 P0 3 . 



The relation between the conductivities of the acid 

 before and after hydrolysis is interesting. At the lower 

 dilutions the conductivity of the pure hypophosphoric 

 acid is larger than that of the equimolecular mixture of 

 phosphorous and phosphoric acids which is formed by 

 its hydrolysis, while at the higher dilutions this relation 

 is reversed. At a dilution slightly above 64 liters 

 (referred to H 4 P 2 6 ) the conductivity would not change 

 as the hydrolysis progressed, at higher dilutions it would 

 increase and at lower dilutions it would decrease. 

 Except in proximity to this special dilution it should 

 therefore be possible to determine the rate of hydrolysis 



