Estimate the fraction of molecular volume to the actual volume occupied by oxygen gas at STP. Take the diameter of an oxygen molecule to be `3 Å`.

Explanation

To estimate the fraction of molecular volume to the actual volume occupied by oxygen gas at STP, we can follow these steps:

### Step 1: Calculate the volume of a single oxygen molecule.
The volume \( V \) of a single molecule can be calculated using the formula for the volume of a sphere:

\[ V = \frac{4}{3} \pi r^3 \]
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