Which of these is true regarding the gaseous state? 

Options

A. Gases have the least inter-particle motion
B. Gases can never be heterogeneously mixed
C. Particles of a gas have the highest mobility
D. All of these are correct

Answer

To determine which of the given statements regarding the gaseous state is true, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- **Statement:** Gases have the least inter-particle motion.
- **Analysis:** This statement is incorrect. In the gaseous state, particles have the highest inter-particle motion due to negligible intermolecular forces of attraction. Gaseous particles move freely and collide with each other and the walls of their container.
- **Conclusion:** This statement is false.

2. **Evaluate the Second Statement:**
- **Statement:** Gases can never be heterogeneously mixed.
- **Analysis:** This statement is also incorrect. While gases typically mix homogeneously, they can form heterogeneous mixtures under certain conditions. For example, mist and fog are examples of heterogeneous mixtures involving gases.
- **Conclusion:** This statement is false.

3. **Evaluate the Third Statement:**
- **Statement:** Particles of a gas have the highest mobility.
- **Analysis:** This statement is correct. Due to negligible intermolecular forces, gas particles can move freely and with high speed. As temperature increases, the kinetic energy of gas particles also increases, leading to greater mobility.
- **Conclusion:** This statement is true.

4. **Final Decision:**
- Based on the analysis, the third statement is the only true statement regarding the gaseous state. Therefore, the correct answer is the third statement.

### Final Answer:
The correct statement regarding the gaseous state is: **Particles of a gas have the highest mobility.**

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