Real gases do not obey ideal gas equation,

Options

A. at low temperature
B. at low pressures
C. at high pressure
D. at high temperature

Explanation

To understand why real gases do not obey the ideal gas equation, we need to analyze the conditions under which deviations from ideal behavior occur. The ideal gas equation is given by:

\[ PV = nRT \]

Where:
- \( P \) = pressure
- \( V \) = volume
- \( n \) = number of moles
- \( R \) = ideal gas constant
- \( T \) = temperature

### Step 1: Understand the Ideal Gas Assumptions
The ideal gas law is based on several assumptions:
1. Gas particles have no volume.
2. There are no intermolecular forces between gas particles.
3. Gas particles are in constant, random motion.
4. Collisions between gas particles are perfectly elastic.

### Step 2: Identify Conditions for Deviations
Real gases deviate from ideal behavior under certain conditions:
- **Low Temperature**: At low temperatures, gas particles have less kinetic energy, leading to increased intermolecular attractions. This causes the gas to occupy less volume than predicted by the ideal gas law.
- **High Pressure**: At high pressures, gas particles are forced closer together, and the volume of the gas particles becomes significant compared to the total volume of the gas. This also leads to deviations from ideal behavior.

### Step 3: Conclusion on Real Gases
Therefore, real gases do not obey the ideal gas equation primarily at:
- Low temperatures (due to increased intermolecular forces).
- High pressures (due to the significant volume of gas particles).

### Final Answer
Real gases do not obey the ideal gas equation at low temperatures and high pressures.