Select the appropriate property of an ideal gas

Options

A. its molecules are infinitesimally small
B. There are no forces of interaction between its molecules
C. It strictly obeys the ideal gas laws
D. All of these

Answer

To select the appropriate property of an ideal gas, we need to analyze the characteristics of an ideal gas based on the information provided.

### Step-by-Step Solution:

1. **Definition of Ideal Gas**: An ideal gas is a theoretical gas composed of many particles that are in constant random motion. The interactions between these particles are negligible.

2. **Molecular Size**: The molecules of an ideal gas are considered to be point particles, meaning their volume is negligible compared to the volume of the gas itself. This aligns with the first property mentioned.

3. **No Intermolecular Forces**: In an ideal gas, it is assumed that there are no forces of attraction or repulsion between the molecules. This means that the molecules do not interact with each other, which is a key characteristic of an ideal gas.

4. **Elastic Collisions**: The collisions between the molecules of an ideal gas are perfectly elastic. This means that there is no loss of kinetic energy during collisions, which is another important property of ideal gases.

5. **Obeying Ideal Gas Laws**: Ideal gases strictly follow the ideal gas laws (PV=nRT), which describe the relationship between pressure (P), volume (V), temperature (T), and the number of moles (n) of the gas.

6. **Conclusion**: Based on the properties discussed, we can conclude that all the options provided are true regarding the properties of an ideal gas. Therefore, the correct answer is "All of these".

### Final Answer:
The appropriate property of an ideal gas is that all of the mentioned properties are true.

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