Question

Assertion (A) Cyclohexane is the most stable cycloalkane.
Reason (R) Cyclopropane and cyclobutane are less stable due to angle strain and torsional strain.
The correct answer is

• A. Both (A) and (R) are true but ( R ) is not the correct explanation of (A).
• B. (A) is true but (R) is not true.
• C. (A) is not true but (R) is true.
• D. Both (A) and (R) are true and (R) is the correct explanation of (A).

Answer 1

Answer: (A)

In cycloalkane the heat of combustion of cyclohexane $\left(657.9\, kJ \,mol ^{-1}\right)$ is the lowest hence it is the most stable cycloalkane. Cyclopropane and cyclobutane are less stable due to angle strain and torsional strain, therefore cyclopropane and cyclobutane are reactive cycloalkane.