31 g of ethylene glycol `(C_2H_6O_2)` is dissolved in 600g of water. The freezing point depression of the solution is `(K_f` for water is 1.86 `K Kg mol^-1)`

Options

A. 0 . 77 K
B. 1 . 55 K
C. 4 . 65 K
D. 3 . 10 K

Answer

B

Explanation

`:. Delta T_(t) = K_(f) .(W_(B))/(M_(B))xx (1000)/(W_(A))`
Given,
`W_(B)` (mass of ethylene glycol) = 31 g
`W_(A)` (mass of water) = 600 g
`K_(1)` (for water ) = 186 K kg `mol^(-1)`
and `Mg (for C_(2) H_(6) O_(2)) = 62`
`:. Delta T_(t) = (1.86 xx 31 xx 1000)/(62 xx 600)`
= 155 K