Which of the following statements is not correct

Options

A. Aldehydes and ketones undergo nucleophilic additions
B. Aldehydes and ketones undergo electrophilic substitutions
C. Aldehydes and ketones contains polar carbonyl groups
D. Lower members of aldehydes and ketones are soluble in water due to hydrogen bonding

Answer

To determine which of the following statements is not correct regarding aldehydes and ketones, we will analyze each statement one by one.

### Step 1: Analyze the Statements

1. **Statement 1**: Aldehydes and ketones undergo nucleophilic addition reactions.
- **Analysis**: This statement is correct. Aldehydes and ketones have a carbonyl group (C=O) that is polarized, making them susceptible to nucleophilic attack.

2. **Statement 2**: Aldehydes and ketones undergo electrophilic substitution.
- **Analysis**: This statement is incorrect. Aldehydes and ketones primarily undergo nucleophilic addition reactions rather than electrophilic substitution. Electrophilic substitution is more characteristic of aromatic compounds.

3. **Statement 3**: Aldehydes and ketones contain a polar carbonyl group (C=O).
- **Analysis**: This statement is correct. The carbonyl group is indeed polar due to the difference in electronegativity between carbon and oxygen.

4. **Statement 4**: Lower members of aldehydes and ketones are soluble in water due to hydrogen bonding.
- **Analysis**: This statement is correct. Lower molecular weight aldehydes and ketones can form hydrogen bonds with water, making them soluble.

### Step 2: Identify the Incorrect Statement

From the analysis above, we find that:
- Statement 2 is the only incorrect statement as aldehydes and ketones do not undergo electrophilic substitution.

### Conclusion

The statement that is not correct is **Statement 2**: "Aldehydes and ketones undergo electrophilic substitution."

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