Which gas can most readly liquified

Options

A. `NH_(3)`
B. `CI_(2)`
C. `SO_(2)`
D. `CO_(2)`

Answer

To determine which gas can be most readily liquefied among ammonia (NH3), chlorine (Cl2), sulfur dioxide (SO2), and carbon dioxide (CO2), we need to consider two main factors: the critical temperature and the Van der Waals forces of attraction.

### Step-by-Step Solution:

1. **Understanding Critical Temperature**:
- The critical temperature of a gas is the temperature above which it cannot be liquefied, regardless of the pressure applied. A higher critical temperature means that the gas can be liquefied more easily.

2. **Identifying the Gases**:
- We have four gases to consider: ammonia (NH3), chlorine (Cl2), sulfur dioxide (SO2), and carbon dioxide (CO2).

3. **Comparing Critical Temperatures**:
- We need to look up or recall the critical temperatures of these gases:
- Ammonia (NH3): ~132 °C
- Chlorine (Cl2): ~ -34 °C
- Sulfur Dioxide (SO2): ~ 157 °C
- Carbon Dioxide (CO2): ~ 31 °C
- From this comparison, we see that sulfur dioxide (SO2) has the highest critical temperature.

4. **Considering Van der Waals Forces**:
- The Van der Waals forces of attraction (represented by the symbol A in the Van der Waals equation) also play a significant role in the liquefaction of gases. A higher value of A indicates stronger intermolecular forces, which facilitate liquefaction.
- Among the gases, sulfur dioxide (SO2) has significant dipole-dipole interactions due to its molecular structure, contributing to a higher value of A.

5. **Conclusion**:
- Based on the critical temperature and the strength of Van der Waals forces, sulfur dioxide (SO2) can be most readily liquefied among the given options.

### Final Answer:
**Sulfur Dioxide (SO2)** is the gas that can be most readily liquefied.