The number of atoms in one molecule of oxygen is ___________.

Explanation

To determine the number of atoms in one molecule of oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Formula of Oxygen**:
The molecular formula for oxygen is O₂. This indicates that each molecule of oxygen consists of two oxygen atoms.

2. **Count the Atoms in the Formula**:
In the formula O₂, the subscript "2" indicates that there are two atoms of oxygen present in one molecule.

3. **Conclusion**:
Therefore, the number of atoms in one molecule of oxygen (O₂) is 2.

### Final Answer:
The number of atoms in one molecule of oxygen is **2**.

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