The freezing point of a solution prepared from `1.25 g` of non-electrolyte and `20 g` of water is `271.9 K`. If the molar depression constant is `1.86 K mol^(-1)`, then molar mass of the solute will be

Options

A. 105.7
B. 106.7
C. 115.3
D. 93.9

Answer

A

Explanation

`M = (K_(f) xx 1000 xx w)/(W xx DeltaT_(f))`
`= (1.86 xx 1000 xx 1.25)/(20 xx 1.1) = 105.68 ~~ 105.7`