Question

Assertion :When 'a' mL of a 0.1 molal urea solution is mixed with another 'b' mL of 0.2 molal glucose solution, the boiling point of the solution is no different from the boiling points of the samples prior to mixing but if 'a' mL of 0.1 molal urea is mixed with 'b' mL of 0.1 molal $HF$, the boiling point of the mixture is different from the boiling points of the separate samples. Reason: $HF$ is an electrolyte (weak) whereas glucose is non electrolyte.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Assertion is incorrect but Reason is correct

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

$HF$ is a weak electrolyte and its degree of dissociation changes with change in concentration.Hence, the boiling point of mixture is different from that of separate samples.
Glucose is a non electrolyte. Urea is also a non electrolyte. Hence, the boiling point of mixture is same as that of separate samples.