Give two chemical tests to distinguish between benzaldehyde and benzoic acid.

Explanation

To distinguish between benzaldehyde and benzoic acid, we can perform two chemical tests: the sodium bicarbonate test and the litmus test. Here’s a step-by-step solution:

### Step 1: Sodium Bicarbonate Test
1. **Take a sample of the compound**: Prepare two separate test tubes, one containing benzaldehyde and the other containing benzoic acid.
2. **Add sodium bicarbonate (NaHCO₃)**: To each test tube, add a small amount of sodium bicarbonate.
3. **Observe the reaction**:
- **For benzoic acid**: You will observe the evolution of carbon dioxide (CO₂) gas, which will produce brisk effervescence (bubbles).
- **For benzaldehyde**: There will be no reaction, and no gas will be evolved.
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