Which of the following should be most volatile?

• A C H₃ C H₂ C H₂ N H₂
• B (C H₃)₃ N
• C C H₃ C H₂ - H N - C H₃
• D C H₃ C H₂ C H₃

To determine which compound is likely to be the most volatile, we need to consider their molecular structures and the types of intermolecular forces present.

Factors Influencing Volatility

Volatility is influenced by:

• Molecular Weight: Lighter molecules tend to be more volatile.
• Intermolecular Forces: Weaker forces (like London dispersion forces) lead to higher volatility.
• Branching: More branched molecules generally have lower boiling points and are more volatile.

Analysis of Each Compound

Let's analyze the given options:

• A: C₃H₇NH₂ - This compound has hydrogen bonding due to the amine group, which can reduce volatility.
• B: (C₃H₉)₃N - This is a tertiary amine with more branching, likely increasing volatility.
• C: C₃H₇ - A simple hydrocarbon with weaker forces, suggesting higher volatility.
• D: C₃H₇C₃ - This is also a hydrocarbon but may have more complex interactions.

Conclusion

Among these, compound C (C₃H₇) is expected to be the most volatile due to its simple structure and weaker intermolecular forces compared to the others.