Out of the five isomeric hexanes, the isomer that can give two monochlorinated compounds is:

Options

A. (a) 2,3-Dimethylbutane
B. (b) 2,2-Dimethyl butane
C. (c) 2-Dimrthyl pentane
D. (d) n-Hexane

Explanation

To determine which isomer of hexane can yield two monochlorinated compounds, we need to analyze the isomers of hexane and their potential for chlorination. The five isomeric hexanes are:

1. n-Hexane (straight-chain)
2. 2-Methylpentane
3. 3-Methylpentane
4. 2,2-Dimethylbutane
5. 2,3-Dimethylbutane

We will evaluate each isomer to see how many distinct monochlorinated products can be formed.

### Step-by-Step Solution:

**Step 1: Analyze 2,3-Dimethylbutane**
- Structure:
```
CH3
|
CH3 - C - CH - CH3
|
CH3
```
- Chlorination Sites:
- Chlorination can occur at the following positions:
- Carbon 1 (C1)
- Carbon 2 (C2)
- Carbon 3 (C3)
- Carbon 4 (C4)

- **Monochlorinated Products:**
1. Chlorination at C1: 1-chloro-2,3-dimethylbutane
2. Chlorination at C2: 2-chloro-2,3-dimethylbutane
3. Chlorination at C3: 2-chloro-2,3-dimethylbutane (same as C2)
4. Chlorination at C4: 1-chloro-2,3-dimethylbutane (same as C1)

- **Distinct Products:**
- We find that chlorination at C1 and C2 gives us two distinct monochlorinated products.

**Step 2: Analyze Other Isomers**
- **n-Hexane:**
- Can yield 6 distinct products due to symmetrical nature.

- **2-Methylpentane:**
- Can yield 4 distinct products due to the presence of chiral centers.

- **3-Methylpentane:**
- Can yield 4 distinct products due to the presence of chiral centers.

- **2,2-Dimethylbutane:**
- Can yield 4 distinct products due to symmetrical nature and chiral centers.

### Conclusion:
Among the five isomers, **2,3-Dimethylbutane** is the only isomer that can yield exactly **two distinct monochlorinated compounds**.

### Final Answer:
The isomer that can give two monochlorinated compounds is **2,3-Dimethylbutane**.

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