`6 xx 10^(20)` molecules are present in a sample of hydrogen gas, having volume V at S. T.P. Find the volume of oxygen at S. T.P. which contains `3 xx 10^(24)` molecules.

Explanation

To solve the problem step by step, we will follow the principles of the mole concept and the relationship between the number of molecules and the volume of gas at standard temperature and pressure (STP).

### Step 1: Calculate the number of moles of hydrogen gas
We know that the number of molecules (N) can be converted to moles (n) using Avogadro's number (NA = \(6.022 \times 10^{23}\) molecules/mol).

Given:
- Number of molecules of hydrogen gas = \(6 \times 10^{20}\)

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