Which of the following graph is correct for real gases other than hydrogen and helium at `0^(@)` ?

Options

A.
B.
C.
D.

Answer

To determine the correct graph for real gases other than hydrogen and helium at 0°C, we need to understand the behavior of real gases compared to ideal gases under different conditions.

### Step-by-Step Solution:

1. **Understanding Ideal vs. Real Gases**:
- Ideal gases follow the ideal gas law perfectly under all conditions. They have no intermolecular forces and occupy no volume.
- Real gases deviate from this behavior, especially at high pressures and low temperatures, due to intermolecular forces and the finite volume of gas molecules.

2. **Behavior of Real Gases at 0°C**:
- At 0°C, real gases will not behave perfectly like ideal gases. They will show deviations from the ideal gas law.
- Real gases behave more like ideal gases at high temperatures and low pressures. At low temperatures and high pressures, they deviate significantly.

3. **Graphical Representation**:
- The graph typically plots pressure (P) on the y-axis and volume (V) on the x-axis.
- For ideal gases, the graph is linear, indicating that pressure is inversely proportional to volume (PV = constant).
- For real gases, at low temperatures and moderate pressures, the graph will show a curve that deviates from the ideal gas line.

4. **Analyzing the Options**:
- **Option A**: If the ideal gas line is behind the real gas line, it suggests that the real gas behaves better than the ideal gas, which is incorrect.
- **Option B**: If both lines are parallel, it implies that real gases behave exactly like ideal gases, which is not true at low temperatures.
- **Option C**: This option shows real gas behavior deviating from ideal gas behavior, which is expected at 0°C.
- **Option D**: Similar to option A, it implies incorrect behavior.

5. **Conclusion**:
- The correct graph for real gases other than hydrogen and helium at 0°C is **Option C**, as it accurately represents the deviation of real gases from ideal behavior.