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 dissociated in 1 kg of water is : (`K_(f) = 1.86` K kg `mol^(-1)`)

Options

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

Answer

B

Explanation

Van't Hoff's factor (i)for `Na_(2) SO_(4) = 3 `
`:.Delta T_(f) =(i) K_(f) m =3 xx 1.80 xx(0.01)/( 1) =0.0558 K `