The compound with the highest boiling point is

Options

A. n - Hexane
B. n - Pentane
C. 2, 2 - Dimethylpropane
D. 2 - Methylbutane

Explanation

To determine which compound has the highest boiling point among the given options, we need to consider the molecular mass and the structure of the compounds. Here’s a step-by-step solution:

### Step 1: Identify the Compounds
The compounds mentioned are:
1. n-Hexane (C6H14)
2. n-Pentane (C5H12)
3. 2,2-Dimethylpropane (C5H12)
4. 2-Methylbutane (C5H12)

### Step 2: Compare the Molecular Mass
- **n-Hexane** has 6 carbon atoms, thus it has a higher molecular mass compared to the other compounds.
- **n-Pentane**, **2,2-Dimethylpropane**, and **2-Methylbutane** each have 5 carbon atoms, resulting in lower molecular masses compared to n-Hexane.

### Step 3: Analyze the Structure
- n-Hexane is a straight-chain alkane, which generally has a higher boiling point due to greater surface area for van der Waals forces.
- The other compounds (n-Pentane, 2,2-Dimethylpropane, and 2-Methylbutane) are branched or have fewer carbon atoms, which typically results in lower boiling points due to reduced surface area.

### Step 4: Conclusion
Given that n-Hexane has the highest molecular mass and is a straight-chain alkane, it will have the highest boiling point among the options provided.

**Final Answer: n-Hexane has the highest boiling point.**

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