Equilibrium constants are given (in atm) for the following reactions at 0°C :
`SrCl_(2). 6H_(2)O(s)hArrSrCl_(2).2H_(2)O(s) + 4H_(2)O(g)`
`K_(p) = 5 x× 10^(-12)`
`Na_(2)HPO_(4).12H_(2)O(s)hArrNa_(2)HPO_(4). 7H_(2)O (s)+ 5H_(2)O(g)K_(p) = 2.43 x× 10^(-13)`
`Na_(2)SO_(4).10H_(2)O(s)hArrNa_(2)SO_(4)(s) + 10 H_(2)O(g)`
`K_(p) = 1.024 x× 10^(-27)`
The vapour pressure of water at 0° C is 4.56 torr.
Which is the most effective drying agent at 0°C

Options

A. `SrCl_(2).2H_(2)O`
B. `Na_(2)HPO_(4). 7H_(2)O`
C. `Na_(2)SO_(4)`
D. all equally

Answer

A