Find the average momentum of molecules of hydrogen gas in a container at temperature `300K`.

Explanation

To find the average momentum of hydrogen gas molecules in a container at a temperature of 300 K, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Motion of Gas Molecules**:
- Gas molecules, including hydrogen, move in random directions. This random motion makes it challenging to determine the velocity of an individual molecule.

2. **Defining Average Velocity**:
- The average velocity (\( V_{avg} \)) of gas molecules is calculated by taking the sum of the velocities of all molecules and dividing by the number of molecules (\( n \)):
\[ V_{avg} = \frac{V_1 + V_2 + ... + V_n}{n} \]
- However, because the molecules are moving in random directions, the average velocity of the gas molecules is effectively zero:
\[ V_{avg} = 0 \]

3. **Calculating Average Momentum**:
- The momentum (\( P \)) of a single molecule is given by the formula:
\[ P = m \cdot V \]
where \( m \) is the mass of the molecule and \( V \) is its velocity.
- The average momentum (\( P_{avg} \)) of the gas molecules can be expressed as:
\[ P_{avg} = m \cdot V_{avg} \]
- Since we have established that \( V_{avg} = 0 \), we can substitute this into the equation:
\[ P_{avg} = m \cdot 0 = 0 \]

4. **Conclusion**:
- Therefore, the average momentum of the hydrogen gas molecules in the container at a temperature of 300 K is:
\[ P_{avg} = 0 \]