What is the action of acidified potassium dichromate on hydrogen sulphide `(H_(2)S)` ?

Explanation

To understand the action of acidified potassium dichromate on hydrogen sulfide (H₂S), we can break down the reaction step by step:

### Step 1: Identify the Reactants
The reactants in this reaction are:
- Acidified potassium dichromate (K₂Cr₂O₇ in dilute sulfuric acid, H₂SO₄)
- Hydrogen sulfide (H₂S)

### Step 2: Understand the Reaction Conditions
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