Distinguish on the basis of heating in dry test tube
`CO_2` and `SO_2` (by using a suitable reagent)

Explanation

To distinguish between carbon dioxide (CO₂) and sulfur dioxide (SO₂) based on their reactions when heated in a dry test tube, we can use specific reagents that will react differently with each gas. Here is a step-by-step solution:

### Step 1: Prepare the Test Tubes
- Take two dry test tubes. Label one as "Test Tube A" for carbon dioxide (CO₂) and the other as "Test Tube B" for sulfur dioxide (SO₂).

### Step 2: Introduce the Gases
- In Test Tube A, introduce carbon dioxide (CO₂) gas.
- In Test Tube B, introduce sulfur dioxide (SO₂) gas.
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