Question

Arrange the following compounds in increasing order of their boiling point:
\[ \text{(CH}_3\text{)}_2\text{NH, CH}_3\text{CH}_2\text{NH}_2, \text{CH}_3\text{CH}_2\text{OH} \]

Hint:

Boiling points increase with the strength of intermolecular forces. Alcohols have stronger hydrogen bonding than amines, which leads to higher boiling points.

Answer 1

To solve the problem, we need to arrange the given compounds in increasing order of their boiling points.

1. Understanding the Boiling Points:
Boiling points of compounds are influenced by intermolecular forces such as hydrogen bonding, dipole-dipole interactions, and London dispersion forces. Stronger intermolecular forces usually result in higher boiling points.

2. Analyzing the Compounds:
The given compounds are:
- (CH₃)₂NH (Dimethylamine) 
- CH₃CH₂NH₂ (Ethylamine) 
- CH₃CH₂OH (Ethanol)

3. Boiling Points of Compounds:
- (CH₃)₂NH (Dimethylamine): This compound is a simple amine. It exhibits hydrogen bonding, but it is weaker compared to alcohols. - CH₃CH₂NH₂ (Ethylamine): This is another amine, but it has a slightly higher boiling point than dimethylamine due to its larger molecular size and stronger dipole-dipole interactions. - CH₃CH₂OH (Ethanol): This compound has a hydroxyl group (-OH), which allows for strong hydrogen bonding, leading to a higher boiling point compared to the amines.

4. Order of Boiling Points:
We can now arrange the compounds in increasing order of their boiling points based on the strength of the intermolecular forces:

Increasing Order of Boiling Points:
(CH₃)₂NH < CH₃CH₂NH₂ < CH₃CH₂OH

Final Answer:
The compounds in increasing order of their boiling points are:
(CH₃)₂NH < CH₃CH₂NH₂ < CH₃CH₂OH.