A 0.004 M solution of `Na_(2)SO_(4)` is isotonic with a 0.010 M solution of glucose at same temperature. The apparent degree of dissociation fo `Na_(2)SO_(4)` is

Options

A. 0.25
B. 0.5
C. 0.75
D. 0.85

Answer

C

Explanation

Solution of `Na_(2)SO_(4)` is isotonic with solution of glucose
`pi(Na_(2)SO_(4)" solution")=p(C_(6)H_(12)O_(6)" solution")`
`[1+(n_(NO_(2)SO_(4))-1)alpha_(Na_(2)SO_(4))]C_(Na_(2)SO_(4))RT=1xxC_(C_(6)H_(12)O_(6))xxRT`
`(1+(3-1)alpha_(Na_(2)SO_(4)))xx0.004=0.010`
`alpha_(Na_(2)SO_(4))=0.75=75%`