In which of the following entropy decreases

Options

A. Crystallization of sucrose from the solution
B. Rusting of iron
C. Melting of ice
D. Vaporisation of Camphor

Explanation

To determine in which process entropy decreases, we need to analyze the processes provided in the question. Entropy is a measure of disorder or randomness in a system; thus, a decrease in entropy indicates a transition from a more disordered state to a more ordered state.

**Step-by-Step Solution:**

1. **Understanding Entropy**:
- Entropy (S) is a thermodynamic property that quantifies the amount of disorder or randomness in a system. Higher entropy means more disorder, while lower entropy indicates more order.

2. **Analyzing Each Process**:
- **Crystallization of Sucrose from Solution**:
- When sucrose crystallizes from a solution, the molecules transition from a disordered liquid state to a more ordered solid state. This means that the randomness decreases, and thus, the entropy decreases.

- **Rusting of Iron**:
- Rusting involves the formation of iron oxide from iron and oxygen. This process leads to an increase in disorder as the iron reacts with oxygen and moisture in the environment. Therefore, entropy increases in this process.

- **Melting of Ice**:
- When ice melts, it transitions from a solid state (ordered) to a liquid state (less ordered). This increase in disorder results in an increase in entropy.

- **Vaporization of Camphor**:
- Vaporization involves converting a liquid into a gas. The gaseous state has much higher entropy than the liquid state due to increased molecular motion and disorder. Thus, entropy increases during vaporization.

3. **Conclusion**:
- Among the processes analyzed, the only process where entropy decreases is the **crystallization of sucrose from the solution**.

**Final Answer**: The process in which entropy decreases is the **crystallization of sucrose from the solution**.

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