Question

When concentration of a salt solution is increased,

• A. boiling point increases, while vapour pressure decreases
• B. boiling point decreases, while vapour pressure increases
• C. freezing point decreases, while vapour pressure increases
• D. freezing point increases, while vapour pressure decreases

Answer 1

Answer: (A)

Increase in the concentration of salt solution means more solute (salt) is present and hence, more surface sites are occupied by solute molecules, That's why vapour pressure decreases and a higher temperature is required to boil the solution, i.e. boiling point increases.