When two gases are mixed the entropy :-

Options

A. Remains constant
B. Decreases
C. Increases
D. Becomes zero

Answer

**Step-by-Step Solution:**

1. **Understanding Entropy**: Entropy is a measure of the degree of randomness or disorder in a system. When two gases are mixed, the overall disorder of the system changes.

2. **Mixing of Gases**: When two different gases are mixed, the molecules of each gas will spread out and occupy the available volume. This leads to an increase in the randomness of the system.

3. **Degree of Randomness**: The degree of randomness increases when two gases are mixed because the gas molecules can move freely and occupy more possible positions and energy states.

4. **Effect on Entropy**: Since entropy is directly related to the degree of randomness, an increase in randomness due to the mixing of gases will result in an increase in entropy.

5. **Conclusion**: Therefore, when two gases are mixed, the entropy of the system increases.

**Final Answer**: The correct option is that the entropy increases when two gases are mixed.

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