How many sigma $(\sigma )$ and pi $(\pi )$ bonds are there in ${\text{C}}{{\text{H}}_{\text{3}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{CCC}}{{\text{H}}_{\text{2}}}{\text{COOH}}$?

A. 13$\sigma$ and 5$\pi$

B. 15$\sigma$ and 2$\pi$

C. 15$\sigma$ and 3$\pi$

D. 15$\sigma$ only

C

This was thought to be a hard example “to test student understanding of hybridization and bond types”. This type of question is not new and was answered correctly by 79% of the candidates. All a candidate needs to do is to count the number of $\pi$-bonds.