Question

The cylindrical shape of an alkyne is due to

• A. three sigma $C-C$ bonds
• B. three $\pi\, C-C$ bonds
• C. two sigma $C-C$ and one $\pi C-C $bonds
• D. one sigma $C-C$ and two $\pi C-C $ bonds

Answer 1

Answer: (D)

In alkynes $C \equiv C$ is present, in such bond one sigma and two $\pi$-bonds are present. Sigma bond is formed by sp-hybrid orbitals whereas $\pi$-bonds are formed by unhybridised orbitals. Hence, it shows cylindrical shape.