Benzene hexachloride (BHC) is used as :

Options

A. Dye
B. Antimalarial drug
C. Antibiotic
D. Insecticide

Answer

**Step-by-Step Solution:**

1. **Understanding Benzene Hexachloride (BHC):**
Benzene hexachloride, also known as lindane, is a chemical compound derived from benzene. Its chemical formula is C6H6Cl6, indicating that it contains six chlorine atoms attached to a benzene ring.

2. **Preparation of Benzene Hexachloride:**
Benzene hexachloride is prepared by the chlorination of benzene. This process involves the reaction of benzene (C6H6) with chlorine gas (Cl2) in the presence of a catalyst, typically aluminum chloride (AlCl3), and under specific conditions such as sunlight and elevated temperatures.

3. **Reaction Mechanism:**
- When benzene reacts with chlorine in the presence of AlCl3, it forms chlorobenzene (C6H5Cl).
- Under the influence of sunlight and at a temperature of around 500 Kelvin, benzene can react with three moles of chlorine to fully chlorinate the compound, resulting in benzene hexachloride (C6H6Cl6).

4. **Uses of Benzene Hexachloride:**
Benzene hexachloride is primarily used as an insecticide. It is effective against various pests and has been used in agricultural applications. Additionally, it has applications in shampoos for lice treatment.

5. **Environmental Concerns:**
Despite its effectiveness, the use of benzene hexachloride has become limited due to its harmful effects on the environment. It can bioaccumulate in aquatic organisms, leading to detrimental effects on the food chain and human health.

6. **Conclusion:**
Therefore, the primary use of benzene hexachloride (BHC) is as an insecticide.

**Final Answer:**
Benzene hexachloride (BHC) is used as an insecticide.

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