What is the action of acidified potassium dichromate on sulphur dioxide `(SO_(2))`?

Explanation

To understand the action of acidified potassium dichromate on sulfur dioxide (SO₂), we can break down the process step by step.

### Step 1: Identify the Reactants
The reactants in this reaction are:
- Potassium dichromate (K₂Cr₂O₇), which is an orange compound.
- Sulfur dioxide (SO₂), a colorless gas.
- Sulfuric acid (H₂SO₄), which is used to acidify the solution.

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