Give one good chemical test to distinguish between the following pairs of compounds :
Methanal and ethanal.

Explanation

To distinguish between methanal (formaldehyde) and ethanal (acetaldehyde), we can perform the iodoform test. Here’s a step-by-step solution:

### Step 1: Prepare the reagents
Gather the necessary reagents for the iodoform test, which include iodine (I2) and sodium hydroxide (NaOH).

### Step 2: Take the samples
Take small samples of methanal and ethanal in separate test tubes.

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