Question

Identify the compound having lowest boiling point.

• A. \(\text{H}_{2}\text{O}\)
• B. \(\text{CH}_{2}(\text{OH})\text{-CH}_{2}(\text{OH})\)
• C. \(\text{CH}_{3}-\text{O}-\text{C}_{2}\text{H}_{5}\)
• D. \(\text{C}_{3}\text{H}_{7}-\text{OH}\)

Hint:

Compounds that form intermolecular hydrogen bonds boil at higher temperatures. Look for the one that cannot.

Answer 1

The Correct Option is C

Step 1: Rank by Forces
Ethylene glycol has two O-H groups and the strongest hydrogen bonding, followed by water and propanol.

Step 2: Weakest Forces
The ether lacks hydrogen bonding and has only weak forces.

Step 3: Conclusion
Weaker forces mean lower boiling point, so the ether boils at the lowest temperature.

Final Answer:
The ether has the weakest intermolecular forces and boils lowest. \[ \boxed{\text{(C) }\text{CH}_{3}-\text{O}-\text{C}_{2}\text{H}_{5}} \]