Acetal is produced by reacting alcohol in the presence of dry HCl with

Options

A. Aldehydes
B. Ketone
C. Ether
D. Carboxylic acid

Answer

To determine which compound reacts with alcohol in the presence of dry HCl to produce an acetal, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Acetal Formation**:
Acetals are formed from the reaction of an aldehyde or a ketone with an alcohol. The general reaction involves the addition of an alcohol to the carbonyl group of the aldehyde or ketone, followed by the elimination of water.

2. **Identify the Reactants**:
In this case, we have alcohol (R'OH) and dry HCl as the catalyst. The question asks which compound will react with these to form an acetal.

3. **Consider the Options**:
The options provided are:
- Aldehydes
- Ketones
- Ethers
- Carboxylic acids

4. **Reactions with Aldehydes**:
When an aldehyde (RCHO) reacts with alcohol in the presence of dry HCl, the following steps occur:
- The alcohol attacks the carbonyl carbon of the aldehyde, forming a hemiacetal (RCH(OH)OR').
- Further reaction with more alcohol leads to the formation of the acetal (RCH(OR')2) and the elimination of water.

5. **Reactions with Ketones**:
A similar mechanism occurs with ketones, where the reaction also leads to the formation of an acetal. However, the question specifically asks for the compound that produces an acetal with alcohol in the presence of dry HCl.

6. **Ethers and Carboxylic Acids**:
- Ethers do not react with alcohol to form acetals.
- Carboxylic acids would not yield acetals directly through this reaction.

7. **Conclusion**:
The correct answer is that acetals are produced by reacting alcohol in the presence of dry HCl with **aldehydes**.

### Final Answer:
**Aldehydes** are the compounds that react with alcohol in the presence of dry HCl to produce acetals.

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