Gases possess characteristic critical temperature which depends upon the magnitude of intermolecular forces between the gas particles. Critical temperatures of ammonia and carbon dioxide are 405.5 K and 304.10 K respectively. Which of these gases will liquify first when you start cooling from 500 K to their critical temperature ?

Explanation

To determine which gas will liquefy first when cooling from 500 K to their respective critical temperatures, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Critical Temperature**: The critical temperature of a gas is the temperature above which it cannot be liquefied, regardless of the pressure applied. Below this temperature, the gas can be converted into a liquid.

2. **Identify the Critical Temperatures**:
- Ammonia (NH₃) has a critical temperature of 405.5 K.
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