Question

In which of the following changes entropy decreases.

• A. Crystallization of sucrose from solution
• B. Dissolving sucrose in water
• C. Melting of ice
• D. Vaporization of camphor

Answer 1

Answer: (A)

Crystallization of sucrose from solution

Answer 2

Entropy decreases in crystallisation of sucrose from solution.

It is a measure of randomness or disorder of the system. Greater the randomness, higher is the entropy. Order of randomness or entropy for solid liquid and gas is : gas $>$ liquid $>$ solid.

In dissolving sucrose in water and melting of ice solid state is changing to liquid state, hence entropy increases.

In vaporisation of camphor, solid state is changing to gaseous state, hence entropy increases.

In crystallisation of sucrose from solution, liquid state is changing to solid state, hence entropy decreases.