Give the chemical reaction, when ethanal is heated with HI.

Explanation

To solve the question of what happens when ethanal (acetaldehyde, CH3CHO) is heated with hydrogen iodide (HI), we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are ethanal (CH3CHO) and hydrogen iodide (HI).

### Step 2: Understand the Reaction Conditions
When ethanal is heated with HI, it is often done in the presence of a reducing agent such as red phosphorus. This condition is important as it facilitates the reduction of the aldehyde.

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