Different gases at the same temperature must have

Options

A. Same volume
B. Same pressure
C. Same average KE
D. Same vander Wall's constant

Explanation

To solve the question "Different gases at the same temperature must have," we need to analyze the relationship between temperature and the properties of gases.

### Step-by-Step Solution:

1. **Understanding Temperature**:
- Temperature is a measure of the average kinetic energy of the particles in a gas. When we say that different gases are at the same temperature, it implies that the average kinetic energy of the gas molecules is the same.

2. **Kinetic Energy Formula**:
- The average kinetic energy (KE) of gas molecules can be expressed by the formula:
\[ KE = \frac{3}{2} k T \]
where \( k \) is the Boltzmann constant and \( T \) is the absolute temperature in Kelvin.

3. **Implication of Same Temperature**:
- Since the temperature is constant for all gases, it follows that the average kinetic energy of the molecules in different gases must also be the same. This is because the kinetic energy is directly proportional to the temperature.

4. **Analyzing Other Properties**:
- While the average kinetic energy is the same, other properties such as pressure, volume, and Van der Waals constants can vary among different gases. For example, two gases at the same temperature can have different pressures and volumes depending on the conditions they are in (e.g., container size, amount of gas).

5. **Conclusion**:
- Therefore, the correct conclusion is that different gases at the same temperature must have the same average kinetic energy.

### Final Answer:
Different gases at the same temperature must have the same average kinetic energy.

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