The boiling point of `0.2 mol kg^(-1)` solution of `X` in water is greater than equimolal solution of `Y` in water. Which of the following statements is true in this case?

Options

A. X is undergoing dissociation in water
B. Molecular mass of X is greater than the molecular mass of Y
C. Molecular mass of X is less than the molecular mass of Y
D. Y is undergoing dissociation in water while X undergoes no change

Answer

A

Explanation

`"Molality of solution X = molality of solution Y"`
`0.2mol//kg`
We know that, elevation in the boiling point `(DeltaT_(b))` of a solution is proportional to the molal concentration kof the solution `i.e.DeltaT_(b)proptomorDeltaT_(b)=K_(b)m`
where, m is the molality of the solution and `K_(b)` is molal boiling point constant or ebullioscopic constant.
`:.` Elevation in boiling point,
`DeltaT_(b)=iK_(b)morDeltaT_(b)proptoi`
where, i is van't Hoff's factor
Since, `DeltaT_(b)` of solution X is greater than `DeltaT_(b)` of solution Y. (Observed colligative property is greater than normal colligative property).
`:."i of solution X gt i of solution Y"`
`:.` Solution X undergoing dissociation.