Question

Assertion :Increasing pressure on pure water decreases its freezing point. Reason: Density of water is maximum at $4^{\circ }C$.

• 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 C Assertion is correct but Reason is incorrect

It is true that the freezing point of water. decreases as the pressure decreases. This is because water expands when it freezes, so compressing ice will tend to convert it to more compact liquid water. Thus, increasing the pressure lowers the freezing point. This is exactly the same thing as saying that decreasing the pressure raises the freezing point.

Density of water is maximum at $4^{\circ }C$ although true is not an explanation of assertion.