Main constituent of coal tar is

Options

A. Aliphatic compounds
B. Aromatic compounds
C. Heterocyclic compounds
D. Cycloalkanes

Answer

To determine the main constituent of coal tar, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Coal Tar**:
- Coal tar is a thick, black liquid that is a byproduct of the carbonization of coal. It is produced during the production of coke, which is used in steel manufacturing.

2. **Composition of Coal Tar**:
- Coal tar is a complex mixture that contains a variety of organic compounds. It primarily consists of aromatic hydrocarbons, which are compounds that contain one or more benzene rings.

3. **Identifying Main Constituents**:
- The main constituents of coal tar include:
- Aromatic hydrocarbons such as benzene, naphthalene, anthracene, and phenanthrene.
- Other compounds such as phenols and polycyclic aromatic hydrocarbons (PAHs).

4. **Evaluating Options**:
- Given the options:
- **Option 1**: Aliphatic compounds - This is incorrect as coal tar is not primarily composed of aliphatic compounds.
- **Option 2**: Aromatic compounds - This is correct as aromatic compounds are the main constituents of coal tar.
- **Option 3**: Heterocyclic compounds - While present, these are not the main constituents.
- **Option 4**: Cycloalkanes - These are also not the main constituents of coal tar.

5. **Conclusion**:
- Based on the analysis, the main constituent of coal tar is **aromatic compounds**.

### Final Answer:
The main constituent of coal tar is **aromatic compounds**.

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