`MX_(2)` dissociates into `M^(2+)` and `X^(ө)` ion in an aqueous solution, with a degree of dissociation `(alpha)` of `0.5`. The ratio of the observed depression of freezing point of the aqueous solution to the value of the depression of freezing point in absence of ionic dissociation is

Answer

2

Explanation

`i=(DeltaT)/(K_(f)xxm)=("Observed depression in freezing point")/("Depressin of freezing point in the absence of ionic dissociation")`
`alpha=((i-1)/(n-1))`
`0.5=(i-1)/(3-1)`
(`MX_(2)` gives three ions in aqueous medium, `:. n=3` )
`:. i=2`]