Question

Assertion (A): \( \Delta_{\text{mix}} H \) for an ideal solution is not equal to zero.
Reason (R): A–B interactions in an ideal solution are the same as between A–A and B–B interactions.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

For an ideal solution, \( \Delta_{\text{mix}} H = 0 \) and obeys Raoult’s Law.

Answer 1

The Correct Option is D

In an ideal solution, the enthalpy of mixing (\( \Delta_{\text{mix}} H \)) is zero because intermolecular forces between A–B are equal to those between A–A and B–B. The assertion incorrectly states it is not equal to zero, making it false. The reason correctly describes an ideal solution.