Solution

MO configuration of $C_2$ (12 electrons): $\sigma1s^2\,\sigma^*1s^2\,\sigma2s^2\,\sigma^*2s^2\,\pi2p_x^2=\pi2p_y^2$ Bond order = 2, and both bonds are π bonds, so $C_2$ has only π bonds according to MOT.

Concept diatomic species with only pi bonds

Molecular Orbital Theory in past papers

20 questions from this chapter have appeared across 13 exam years.