Which of the following is not a monovalent functional group.

Options

A. Aldehydic
B. Ketonic
C. Carboxylic
D. Hydroxy

Answer

To determine which of the following is not a monovalent functional group, we first need to understand what a monovalent functional group is. A monovalent functional group is one that has a valency of 1, meaning it can form one bond with another atom or group of atoms.

Let's analyze the given functional groups:

1. **CHO (Aldehyde Group)**:
- The structure of an aldehyde consists of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydrogen atom.
- This carbon atom has one free bond available for bonding with another atom or group.
- Therefore, the aldehyde group is monovalent.

2. **C=O (Ketone Group)**:
- In a ketone, the carbon atom is double-bonded to an oxygen atom and has two free bonds available for bonding with other atoms or groups.
- This means that the ketone group has a valency of 2.
- Therefore, the ketone group is not monovalent; it is bivalent.

3. **Carboxylic Group (COOH)**:
- The carboxylic group consists of a carbon atom double-bonded to one oxygen atom and single-bonded to a hydroxyl group (OH).
- This carbon atom has one free bond available for bonding with another atom or group.
- Therefore, the carboxylic group is monovalent.

4. **Hydroxy Group (OH)**:
- The hydroxy group consists of an oxygen atom bonded to a hydrogen atom.
- The oxygen has one free bond available for bonding with another atom or group.
- Therefore, the hydroxy group is monovalent.

After analyzing all the options, we can conclude that the ketone group (C=O) is the only functional group that is not monovalent.

**Final Answer**: The correct option is the Ketonic Group (B), as it is not a monovalent functional group.

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