Question

The given graph contain two vapour pressure curves, one is of pure solvent and other is of solution (containing non-volatile solute).
Choose the correct statement(s) from the following:

• A. Point A indicates boiling point of pure solvent.
• B. Point B indicates boiling point of pure solvent.
• C. Point A indicates boiling point of solution.
• D. Point B indicates boiling point of solution.

Answer 1

Answer: (A), (D)

Point B indicates boiling point of solution.


When a non volatile solute is added to the pure solvent, the boiling point of solution increases (due to decrease in vapour pressure). This is called elevation in boiling point.
So (a) and (d) are correct.