A gas occupies `500 cm^3` at S.T.P. At what temperature will the volume of the gas be reduced by 20% of its original volume, pressure being constant ?

Explanation

To solve the problem, we will use Charles's Law, which states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature.

### Step-by-Step Solution:

1. **Identify the Initial Conditions:**
- The initial volume \( V_1 = 500 \, \text{cm}^3 \)
- The initial temperature \( T_1 = 273 \, \text{K} \) (Standard Temperature at STP)

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