Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Physical: Solutions

Question:

When attraction between A – B is more than that of A – A and B – B, the solution will show deviation from Raoult’s law:

Options:

Positive

Negative

No

Cannot be predicted

Correct Answer:

Negative

Explanation:

When the attraction between A - B is more than that of A - A and B - B, the solution will show a negative deviation from Raoult's law.

In a solution exhibiting negative deviation, the intermolecular forces between A - B are weaker than those between A - A and B - B. This results in a higher vapor pressure for the components in the mixture compared to what is predicted by Raoult's law.

The weaker A - B interactions allow the components to escape more easily from the liquid phase, leading to a higher partial vapor pressure for each component. As a result, the observed vapor pressure of the components is higher than expected based on their individual mole fractions.

Therefore, the correct answer is (2) Negative deviation from Raoult's law.