A substance ' X ' (1.5 g) dissolved in 150 g of a solvent ' Y ' (molar mass =300 g mol−1) led to an elevation of the boiling point by 0.5 K. The relative lowering in the vapour pressure of the solvent ' Y ' is ____ ×10−2. (nearest integer)
[Given : Kb of the solvent =5.0 K kg mol−1 ]
Assume the solution to be dilute and no association or dissociation of X takes place in solution.
Held on 21 Jan 2026 · Verified 6 Jul 2026.
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