Critical temperature `(T_(C ))` will be maximum for the following gas ?

Options

A. `H_(2)`
B. `He`
C. `N_(2)`
D. `NH_(3)`

Explanation

To determine which gas has the maximum critical temperature (Tc), we need to understand the concept of critical temperature and the factors that influence it.

### Step-by-Step Solution:

1. **Understand Critical Temperature (Tc)**:
- Critical temperature is defined as the temperature above which a gas cannot be liquefied, regardless of the pressure applied.

2. **Identify the Factors Affecting Tc**:
- The critical temperature is influenced by the strength of intermolecular forces of attraction in the gas. Stronger intermolecular forces lead to higher critical temperatures, while weaker forces result in lower critical temperatures.

3. **Analyze the Given Gases**:
- Let's consider the gases typically mentioned in such questions: H2, He, CO2, and NH3.
- H2 and He are both non-polar gases with weak intermolecular forces (London dispersion forces), leading to low critical temperatures.
- CO2, being a polar molecule, has stronger intermolecular forces (dipole-dipole interactions) than H2 and He, resulting in a higher critical temperature.
- NH3 has strong hydrogen bonding, which is a significant type of intermolecular force, leading to an even higher critical temperature than CO2.

4. **Compare the Critical Temperatures**:
- Based on the strength of intermolecular forces:
- H2 and He: Low Tc (weak forces)
- CO2: Moderate Tc (stronger forces than H2 and He)
- NH3: High Tc (strong hydrogen bonding)

5. **Conclusion**:
- Among the gases listed, NH3 has the strongest intermolecular forces due to hydrogen bonding, which results in the highest critical temperature.

### Final Answer:
The gas with the maximum critical temperature (Tc) is **NH3** (Ammonia).