Chemistry · Organic chemistry – some basic principles and techniques

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Free rotation of atoms or groups of atoms about a carbon-carbon double bond (\( \text{C}=\text{C} \)) is restricted. Reason (R): Rotation of one \( -\text{CH}_2 \) fragment with respect to the other in ethene disrupts the maximum parallel sideways overlap of unhybridised \( 2p \) orbitals forming the \( \pi \)-bond. In the light of the above statements, choose the correct answer from the options given below:

1. A
   Both (A) and (R) are true and (R) is the correct explanation of (A).
2. B
   Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
3. C
   (A) is true but (R) is false.
4. D
   (A) is false but (R) is true.