Equimolal solutions `KCl` and compound `X` in water show depression in freezing point in the ratio of `4:1`, Assuming `KCl` to be completely ionized, the compound `X` in solution must

Options

A. Dissociate to the extent of 50%
B. Hydrolyse to the extent of 80%
C. Dimerize to the extent of 50%
D. Trimerize to the extent of 75%

Explanation

`underset(("p moles"))(KCl)` and `underset(("p moles"))(X)`
`DeltaT_(f)(KCl)=iK_(f)m=2K_(f).m" "," " DeltaT_(f)(X)=K_(f).m=1/4(2K_(f)m)impliesi_(x)=1/2(lt1)`
`1- alpha, alpha//2" "1- alpha, alpha//3`
`i=1-alpha+(alpha)/2=11-(alpha)/2=1/2impliesalpha=100%" "i=1-alpha+(alpha)/3=11-(2alpha)/3=1/2impliesalpha=3/4=75%`