Which of the following does not express the properties of gases ?

Options

A. Gases are highly compressible.
B. Gases exert pressure equally in all directions .
C. Gases have much higher density then liquids and solids .
D. Gases mix evenly and completely in all proportions.

Answer

To solve the question "Which of the following does not express the properties of gases?", we need to analyze the properties of gases and identify which statement is incorrect.

### Step-by-Step Solution:

1. **Understand the Properties of Gases**:
- Gases are highly compressible.
- Gases exert pressure equally in all directions.
- Gases are less dense than liquids and solids.
- Gases mix evenly and completely in all proportions.

2. **Evaluate Each Statement**:
- **Statement A**: "Gases are highly compressible."
- This is true. Gases can be compressed significantly due to the large amount of space between particles.
- **Statement B**: "Gases exert pressure equally in all directions."
- This is also true. The particles in a gas move freely and collide with the walls of their container, exerting pressure uniformly.
- **Statement C**: "Gases are much denser than liquids and solids."
- This statement is false. Gases are actually less dense than both liquids and solids.
- **Statement D**: "Gases mix evenly and completely in all proportions."
- This statement is true. Gases will diffuse and mix uniformly when combined.

3. **Identify the Incorrect Statement**:
- From the evaluation, Statement C is the only one that does not express a property of gases correctly.

4. **Conclusion**:
- The answer to the question is Statement C: "Gases are much denser than liquids and solids."

### Final Answer:
C: Gases are much denser than liquids and solids.

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