The oxidation number of oxygen in hydrogen peroxide is

Explanation

To determine the oxidation number of oxygen in hydrogen peroxide (H₂O₂), we can follow these steps:

### Step 1: Write the chemical formula
The chemical formula for hydrogen peroxide is H₂O₂.

### Step 2: Assign oxidation numbers for known elements
- The oxidation number of hydrogen (H) is typically +1.
- Let the oxidation number of oxygen (O) be represented as \( x \).
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