A functional group is an atom or group of atoms which determines the characteristic functions or chemical properties of a particular organic compound. A functional group contains one or more atoms of elements other than carbon such as oxygen, nitrogen, sulphur and halogens. These atoms are known as heteroatoms and they can replace one or more hydrogen atoms in a hydrocarbon chain. These heteroatoms are responsible for the specific properties of organic compounds regardless of nature and length of carbon chain. These heteroatoms or group of heteroatoms are known as functional groups. The examples of functional groups are - OH, - F,- Cl, -Br, - CHO, - COOH, `- NO_(2), - NH_(2)`, etc.
The functional group of alcohol is

Options

A. `-OH`
B. `-COOH`
C. `-CHO`
D. `-Cl`

Answer

To determine the functional group of alcohol, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Functional Groups**:
- A functional group is a specific group of atoms within a molecule that is responsible for the characteristic chemical reactions of that molecule.

2. **Identify Heteroatoms**:
- Heteroatoms are atoms in a functional group that are not carbon or hydrogen. Common heteroatoms include oxygen, nitrogen, sulfur, and halogens (like fluorine, chlorine, bromine).

3. **Recognize the Functional Group of Alcohol**:
- Alcohols are organic compounds that contain a hydroxyl group (-OH). This group consists of an oxygen atom bonded to a hydrogen atom.

4. **Confirm the Functional Group**:
- The presence of the -OH group in an organic compound indicates that it is an alcohol. This functional group is responsible for the properties and reactions typical of alcohols.

5. **Conclusion**:
- Therefore, the functional group of alcohol is -OH.

### Final Answer:
The functional group of alcohol is -OH.

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