`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

Explanation

`underset(1)(MX_(2)) +underset(0)(M^(2+))+underset(0)(2X^(-))`
`1-alpha" "alpha" " 2 alpha`
`i=1+2alpha=2`
Therefore the ratio of observed depression of freezing point of the aqueous solution to the value of the depression of freezing point in the absence of ionic dissociation is 2 : 1.