Question

a single bond, compared to a double bond.
answer:
a is longer.
b is stronger.
c has a higher bond dissociation energy.
d is not capable of rotation.

Explanation:

• Bond length: Double bonds have more electron density between atoms, pulling them closer. So single bonds are longer.
• Bond strength and bond dissociation energy: Double bonds are stronger (higher bond dissociation energy) than single bonds as there are more bonds (e.g., one sigma and one pi in double vs one sigma in single).
• Rotation: Double bonds restrict rotation (due to pi - bond overlap), single bonds allow rotation.

Answer:

A. is longer.