Aldehydes are isomeric with

Options

A. ketones
B. Ethers
C. Alcohols
D. Fatty acids

Explanation

To determine which compounds are isomeric with aldehydes, we need to understand the definition of isomerism and the structure of aldehydes.

### Step-by-Step Solution:

1. **Understanding Aldehydes**:
- Aldehydes have the general formula \( RCHO \), where \( R \) is a hydrocarbon group. The carbonyl group (C=O) is at the end of the carbon chain.

2. **Identifying Isomeric Compounds**:
- Isomeric compounds must have the same molecular formula but different structural formulas. This means they can have different functional groups or arrangements of atoms.

3. **Analyzing the Options**:
- **Option A: Ketones**:
- Ketones have the general formula \( RC(=O)R' \). For example, the simplest ketone is acetone, \( CH_3COCH_3 \).
- An aldehyde with three carbons is \( CH_3CH_2CHO \) (propionaldehyde). Both have the same molecular formula \( C_3H_6O \), hence they are isomers.

- **Option B: Ethers**:
- Ethers have the general formula \( ROR' \). For example, dimethyl ether is \( CH_3OCH_3 \).
- An aldehyde with two carbons is \( CH_3CHO \) (acetaldehyde). The molecular formula for dimethyl ether is \( C_2H_6O \), which is different from \( C_2H_4O \) (the formula for acetaldehyde). Thus, they are not isomers.

- **Option C: Alcohols**:
- Alcohols have the general formula \( ROH \). For example, ethanol is \( CH_3CH_2OH \).
- An aldehyde with two carbons is \( CH_3CHO \). The molecular formula for ethanol is \( C_2H_6O \), which differs from \( C_2H_4O \). Therefore, they are not isomers.

- **Option D: Carboxylic Acids**:
- Carboxylic acids have the general formula \( RCOOH \). For example, acetic acid is \( CH_3COOH \).
- An aldehyde with two carbons is \( CH_3CHO \). The molecular formula for acetic acid is \( C_2H_4O_2 \), which is different from \( C_2H_4O \). Hence, they are not isomers.

4. **Conclusion**:
- The only option that is isomeric with aldehydes is **Option A: Ketones**.