Question

For which of the following processes, total entropy of universe increases.

• A. Melting one mole of ice to water at $0^{\circ }C$
• B. Freezing one mole of water to ice at $0^{\circ }C$
• C. Freezing one mole of water to ice at $-{10}^{\circ }C$
• D. Melting one mole of ice at ${10}^{\circ }C$ into water

Answer 1

Answer: (C), (D)

The correct options are
C Freezing one mole of water to ice at $-{10}^{\circ }C$
D Melting one mole of ice at ${10}^{\circ }C$ into water

As we know,

In melting process, solid convert into more free form water so entropy of universe increases in melting one mole of ice at ${10}^{\circ }C$ into water.

Also natural water freezes at $0^o$ C so in freezing one mole of water to ice at $-{10}^{\circ }C$ entropy increases.