The expanded form of DDT is

Options

A. dichloro diphenyl trichloroethane
B. dichloro diethyl trichlooroethane
C. dichloro dipyrdyl trichloroethane
D. dichloro diphenyl tetrachloroacetate.

Answer

### Step-by-Step Text Solution:

1. **Understanding DDT**: DDT is a chemical compound commonly known for its use as a pesticide. Its chemical formula is C14H9Cl5, indicating it contains 14 carbon atoms, 9 hydrogen atoms, and 5 chlorine atoms.

2. **Analyzing the Options**: The question provides four options for the expanded form of DDT:
- A) Dichlorodiphenyl trichloroethane
- B) Dichlorodiethyl trichloroethane
- C) Dichlorodipyridyl trichloroethane
- D) Dichlorodiphenyl tetrachloroacetate

3. **Identifying the Structure**: To determine the correct expanded form, we need to visualize the structure of DDT. It consists of two benzene rings connected by an alkane chain, with chlorine atoms attached to the structure.

4. **Naming the Components**:
- The term "dichloro" indicates the presence of two chlorine atoms.
- "Diphenyl" refers to the two benzene rings.
- "Trichloro" indicates three chlorine atoms attached to the ethane part of the molecule.
- "Ethane" refers to the two-carbon chain connecting the benzene rings.

5. **Conclusion**: Based on the structure and the naming conventions, the correct expanded form of DDT is **Dichlorodiphenyl trichloroethane**, which corresponds to option A.

### Final Answer:
The expanded form of DDT is **Dichlorodiphenyl trichloroethane** (Option A).

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