Why are the gases helium and hydrogen not liquefied at room temperature by applying very high pressure ?

Explanation

To understand why helium and hydrogen cannot be liquefied at room temperature even under very high pressure, we need to consider the concept of critical temperature.

### Step-by-Step Solution:

1. **Understanding Critical Temperature**:
- The critical temperature (Tc) of a gas is the temperature above which it cannot be liquefied, regardless of the pressure applied.

2. **Critical Temperatures of Hydrogen and Helium**:
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