Give one chemical test to distinguish between pair of compounds
Formic acid and acetic acid.

Explanation

To distinguish between formic acid (HCOOH) and acetic acid (CH3COOH), we can use the following chemical test:

### Step-by-Step Solution:

1. **Identify the Test**: We will use Tollens' test, also known as the silver mirror test, to differentiate between formic acid and acetic acid.

2. **Prepare Tollens' Reagent**: Tollens' reagent is an ammoniacal silver nitrate solution, which can be prepared by mixing silver nitrate (AgNO3) with ammonia (NH3) in water.

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