Question

Assertion : When ice and water are kept in a perfectly insulated thermos flask at $273\, K$ and the atmospheric pressure, there is no change in mass of ice and water.
Reason : The system is in static equilibrium.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (C)

There is no change in mass of ice and water, as rates of transfer of molecules from ice into water and of reverse transfer from water into ice are equal at atmospheric pressure and $273\,K$. The system is in dynamic equilibrium.