Dominance of strong repulsive forces among the molecules of the
gas (`Z =` compressibility factor)

Options

A. depends on Z and indicated by Z=1
B. depends on Z and indicated by `Zgt1`
C. depends on Z and indicated by `Zlt1`
D. is indendent of Z.

Explanation

To solve the question regarding the dominance of strong repulsive forces among the molecules of a gas and its relationship to the compressibility factor (Z), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Compressibility Factor (Z)**:
- The compressibility factor (Z) is defined as the ratio of the molar volume of a real gas to the molar volume of an ideal gas at the same temperature and pressure.
- Mathematically, Z = (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.

2. **Identifying the Effect of Strong Repulsive Forces**:
- Strong repulsive forces among gas molecules prevent them from coming closer together.
- This means that when the gas is compressed, the volume does not decrease as much as expected due to these repulsive interactions.

3. **Analyzing the Implications on Volume**:
- If the repulsive forces are strong, the decrease in volume upon compression will be less than what is predicted by the ideal gas law.
- Therefore, the actual volume of the gas will be greater than the volume predicted for an ideal gas under the same conditions.

4. **Determining the Value of Z**:
- Since the actual volume is greater than the ideal volume, the compressibility factor Z will be greater than 1 (Z > 1).
- This indicates that the gas is less compressible than an ideal gas due to the dominance of repulsive forces.

5. **Conclusion**:
- Based on the above analysis, we conclude that when strong repulsive forces dominate, the compressibility factor (Z) will be greater than 1.

### Final Answer:
The dominance of strong repulsive forces among the molecules of the gas indicates that the compressibility factor (Z) is greater than 1.