NEETChemistrySolutions
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): A solution formed by adding carbon disulfide to acetone shows negative deviation from Raoult's law. Reason (R): In a mixture of carbon disulfide and acetone, the dipolar interactions between solute-solvent molecules are weaker than the respective interactions among the solute-solute and solvent-sol
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A)
- BBoth (A) and (R) are true but (R) is not the correct explanation of (A)
- C(A) is true but (R) is false
- D(A) is false but (R) is true
Correct answer
D. (A) is false but (R) is true
Step-by-step solution
Assertion (A) is false because a solution of carbon disulfide and acetone exhibits a positive deviation from Raoult's law, not a negative deviation. Reason (R) is true. According to Raoult's law, positive deviation occurs when the new solute-solvent (A-B) interactions are weaker than the pure component (A-A and B-B) interactions. In the case of carbon disulfide and acetone, the dipolar interactions between the solute and solvent molecules are indeed weaker than the interactions in the pure liquids, which leads to t