The total number of benzene derivatives with molecular formula `C_(6)H_(3)Cl_(3)` is :

Options

A. 2
B. 3
C. 4
D. 5

Answer

To determine the total number of benzene derivatives with the molecular formula C6H3Cl3, we can follow these steps:

### Step 1: Understand the Structure
The molecular formula C6H3Cl3 indicates that we have a benzene ring (C6H6) with three hydrogen atoms replaced by chlorine atoms. This means we have a benzene derivative.

**Hint:** Remember that benzene has a stable hexagonal structure with alternating double bonds.

### Step 2: Identify Possible Substitutions
In benzene, the positions of the chlorine atoms can vary. The positions on the benzene ring are numbered as follows:

```
1
/ \
6 2
| |
5---3
\ /
4
```

We can replace three of the hydrogen atoms with chlorine atoms at different positions.

**Hint:** Consider the symmetry of the benzene ring when placing the chlorine atoms.

### Step 3: Count the Isomers
We can place the three chlorine atoms in different positions. The possible arrangements are:

1. **1,2,3-Trichlorobenzene** (Chlorines at positions 1, 2, and 3)
2. **1,2,4-Trichlorobenzene** (Chlorines at positions 1, 2, and 4)
3. **1,3,5-Trichlorobenzene** (Chlorines at positions 1, 3, and 5)
4. **1,3,4-Trichlorobenzene** (Chlorines at positions 1, 3, and 4)
5. **1,2,5-Trichlorobenzene** (Chlorines at positions 1, 2, and 5)

However, some of these arrangements may lead to the same compound due to symmetry.

After analyzing the combinations, we find that:

- **1,2,3-Trichlorobenzene**
- **1,2,4-Trichlorobenzene**
- **1,3,5-Trichlorobenzene**
- **1,3,4-Trichlorobenzene**
- **1,2,5-Trichlorobenzene**

### Step 4: Final Count
After careful consideration of the unique arrangements, we conclude that there are **4 unique isomers** of C6H3Cl3.

**Final Answer:** The total number of benzene derivatives with the molecular formula C6H3Cl3 is **4**.

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