When `20` g of naphthoic acid `(C_(11)H_(8)O_(2))` is dissolved in 50 g of benzene (`K_(f) = 1.72 K "kg" mol^(-1)`) , a freezing point depression of `2` K is observed. The Van't Hoff factor (i) is :

Options

A. 0.5
B. 1
C. 2
D. 3

Answer

A

Explanation

For electrolyte solution, `Delta T_(f) =iK_(f)m`
i.e., `2 = I xx 1.72 xx ( 20)/( 172 ) xx ( 1000)/( 50) implies I = 0.5 `