Give a test to detect the presence of SO2 gas?

Explanation

To detect the presence of sulfur dioxide (SO2) gas, we can use a simple test involving potassium permanganate (KMnO4) solution. Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Preparation of the Test Solution**:
- Prepare an acidified potassium permanganate solution. This is done by adding a few drops of dilute sulfuric acid (H2SO4) to a solution of potassium permanganate (KMnO4). The solution will turn a violet color due to the presence of permanganate ions (MnO4^-).

2. **Passing SO2 Gas**:
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