Balance the chemical equation by the oxidation number method.
(vii) `H_(2)O_(2) + PbS to PbSO_(4) + H_(2)O`

Explanation

To balance the chemical equation \( H_2O_2 + PbS \rightarrow PbSO_4 + H_2O \) using the oxidation number method, follow these steps:

### Step 1: Assign Oxidation Numbers
- In \( H_2O_2 \) (hydrogen peroxide), the oxidation number of oxygen is \(-1\).
- In \( PbS \) (lead sulfide), the oxidation number of lead (Pb) is \(+2\) and sulfur (S) is \(-2\).
- In \( PbSO_4 \) (lead sulfate), the oxidation number of lead (Pb) is \(+2\) and sulfur (S) is \(+6\).
- In \( H_2O \) (water), the oxidation number of oxygen is \(-2\).

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