Question

Which molecule has only pi bonds according to molecu;ar orbital theory

Answer 1

C2 molecules have been found in vapour state. Their double bonds are made of two pi bonds because four electrons need to be accomodated in each bond.

Pi bond: covalent bond resulted due to the sidewise overlapping of the orbitals is referred to as the pi bond. Sigma bond can exist independently whereas the pi bond cannot exist independently. Pi bond can be formed along with the sigma bond.

Answer 2

Molecular Orbital Theory shows that there are two sets of paired electrons in a degenerate pi bonding set of orbitals. This gives a bond order of 2, meaning that there should exist a double bond between the two carbons in a C2 molecule.