Assertion (A) Cyclohexane is the most stable cycloalkane. Reason (R) Cyclopropane and cyclobutane are less…
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
Both (A) and (R) are true but (R) is not the correct explanation of (A).
(A) is true but (R) is not true.
(A) is not true but (R) is true.
Both $(A)$ and $(R)$ are true and $(R)$ is the correct explanation of (A).
Solution
In cycloalkane the heat of combustion of cyclohexane $\left(657.9 \mathrm{~kJ} \mathrm{~mol}^{-1}\right)$ 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.