In winter, the normal temperature in Kashmir valley is ` - 12^(@)` C . Is a `25% ` by mass of an aqueous solution of ethylene glycol (molar mass = 62) suitable for car radiator . `K_(f)` for water is `1 . 86 Km^(-1)`

Answer

`Delta T_(f) = 10, K , No`

Explanation

Let Mass of solution = 100 g
`:.` Mass of ethlene glycol, `W_(B) = 25 g`
Mass of water
`W_(A) = 100 - 25`
= 75 g = 0. 0 75 kg
`K_(f) = 1 . 86 K . m^(-1)`
`= 1. 86 K kg mol^(-1)`
`M_(B) = 62 g mol^(-1)`
`Delta T_(f) = K_(f) xx (W_(B))/(M_(B)) xx (1)/(W_(A) (kg))`
`= (1 . 86 K kg mol^(-1) xx 25 g)/( 62 g mol^(-1) xx 0 . 0 75 kg)`
`=(1860 xx 25)/( 62 xx 75) K = 10 K = 10^(@) C `
`:. T_() = T_(f)^(@) - Delta T_(f)`
`= ( 0 . 10)^(@)C = - 10^(@) C`
Thus this aqueous solution will freeze in radiator in Kashmir Valley. No, This solution cannot be used .