Under what conditions to gases show maximum deviations from ideal gas behaviour ?

Options

A. At high temperature and low pressure
B. At low temperature and high pressure
C. At high temperature and high pressure
D. At low temperature and low pressure

Explanation

### Step-by-Step Solution:

1. **Understanding Ideal Gas Behavior**:
- Ideal gases follow the ideal gas law, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature.
- Ideal gas behavior assumes that gas particles have no volume and do not exert forces on each other.

2. **Conditions for Ideal Gas Behavior**:
- Gases behave ideally at high temperatures and low pressures.
- At high temperatures, the kinetic energy of gas molecules is high, which minimizes intermolecular forces.
- At low pressures, gas molecules are far apart, reducing the effects of volume and intermolecular forces.

3. **Conditions Leading to Deviations**:
- Deviations from ideal gas behavior occur when the assumptions of the ideal gas law are no longer valid.
- This typically happens at low temperatures and high pressures.

4. **Low Temperature**:
- At low temperatures, gas molecules have lower kinetic energy, leading to increased intermolecular attractions.
- These attractions cause the gas to behave less ideally, as the volume of the gas particles and the forces between them become significant.

5. **High Pressure**:
- At high pressures, gas molecules are forced closer together, which makes their volume significant compared to the total volume of the gas.
- The increased density also enhances intermolecular forces, leading to further deviations from ideal behavior.

6. **Conclusion**:
- Therefore, gases show maximum deviations from ideal gas behavior at low temperatures and high pressures.

### Final Answer:
Gases show maximum deviations from ideal gas behavior at **low temperature and high pressure**.

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