If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution,the change in freezing point of water`(DeltaT_(f))`,when `0.01`mole of sodium sulphate is dissoved in `1` kg of water,is `(K_(f)=1.86Kkg mol^(-1))`

Options

A. 0.0186 K
B. 0.0372 K
C. 0.0558 K
D. 0.0744 K

Answer

C

Explanation

Given
`Na_(2)SO_(4)(alpha = 100%)`
i=3
`k_(f)=1.86`
`w//m=0.01`
W = 1 kg = 1000 g
`Delta T_(f)=(1000xx k_(f)xx i xx w)rArr Delta T_(f)=(1000xx1.86xx3xx0.01)/(1000)`
`Delta T_(f)=5.58xx0.01=0.0558 K`