A solution containing 62 g ethylene glycol in 250 g water is cooled to `-10^(@)C`. If `K_(f)` for water is 1.86 K `mol^(-1)`, the amount of water (in g) separated as ice is :

Options

A. 32
B. 48
C. 16
D. 64

Answer

D

Explanation

`Delta T_(f) = (k_(f)xx 1000 xx w_(B))/(w_(A) xx M_(B))`
`Delta T_(f) = 0-(-10) = 10^(@)`
`10 = (1.86 xx 1000 xx 62)/(W_(A) xx 62)`
`w_(A) = (1.86 xx 1000 xx 62)/(10 xx 62 ) = 186 g`
Amount of ice seprated from 250 g of water
=250-186 = 64g`