A fixed mass of gas at STP occupies a certain volume. The gas is heated and allowed to expand to a double its volume with its pressure doubled. What can you say about the average kinetic energy of the gas molecules?

Explanation

To solve the problem, we need to analyze the situation using the ideal gas law and the relationship between temperature and the average kinetic energy of gas molecules.

### Step-by-Step Solution:

1. **Understanding the Initial Conditions**:
- We have a fixed mass of gas at Standard Temperature and Pressure (STP). At STP, the temperature \( T_1 \) is 273.15 K, and the pressure \( P_1 \) is 1 atm.

2. **Using the Ideal Gas Law**:
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