Which among the following has the highest boiling point?

Options

A. `CH_3CH_2CH_2NH_2`
B.
C.
D. `CH_3NH_2`

Answer

To determine which among the given options has the highest boiling point, we need to consider two main factors: molecular weight and molecular structure (specifically, symmetry and branching).

### Step-by-Step Solution:

1. **Identify the Compounds**: First, we need to identify the four options provided in the question. Let's assume they are different amines (e.g., primary, secondary, and tertiary amines).

2. **Consider Molecular Weight**: The boiling point of a compound generally increases with an increase in molecular weight. Therefore, we should compare the molecular weights of the compounds. Higher molecular weight typically leads to higher boiling points.

3. **Evaluate the Type of Amines**:
- Primary amines (1°) generally have higher boiling points than secondary amines (2°), and secondary amines have higher boiling points than tertiary amines (3°). This is due to the ability of primary and secondary amines to form hydrogen bonds more effectively than tertiary amines.

4. **Assess Symmetry and Branching**:
- Linear (unbranched) structures tend to have higher boiling points compared to branched structures. This is because linear molecules can pack more closely together, leading to stronger intermolecular forces.
- For example, if we compare a linear primary amine to a branched secondary amine, the linear primary amine is likely to have a higher boiling point due to its structure allowing for better packing and stronger hydrogen bonding.

5. **Make a Conclusion**: After evaluating the molecular weights, types of amines, and their structures, we can conclude which compound has the highest boiling point. In this case, the linear primary amine will likely have the highest boiling point among the options.

### Final Answer:
Based on the analysis, **Option 1 (the linear primary amine)** has the highest boiling point.

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