Question

Which of the following bonds has the highest energy?

(1)S-S(2)O-O(3)Se-Se(4)Te-Te

Answer 1

The answer is (1) S-S. Sulfur has a tendency to form strong covalent bond as bond is stablized by p$\pi$-d $\pi$ overlapping and it is not there in Oxygen due to the absence of d-orbitals. Also as size of oxygen is not so big, therefore there is lone pair repulsion which make this bond weak.
And due to bigger size of the orbitals in Se and Te, p$\pi$-d $\pi$ bonding is not effective.
Thus S-S has high bond energy.