Question

Which of the following bonds has the highest energy?
(A)$Se - Se$
(B)$Te - Te$
(C)$S - S$
(D)$O - O$

Answer 1

Hint: Generally single bonds are lower energy bonds compared to double bonds. And double bonds are lower energy bonds compared to triple bonds. And also note that ionic bonds are stronger than the covalent bonds.

Complete answer: If we observe the given options, we can notice that all the given elements belong to the same group. So, in this case bond energy is inversely proportional to the bond length. That means if the bond length is increased the bond energy gets decreased because if the bond length is more, then the nucleus cannot attract the outermost electrons strongly and it will show weak attraction force. In oxygen molecules, there is a double bond. Double bond has high strength, so it should have high energy. But due to the small size of oxygen, there will be more inter electronic repulsions and this decreases the bond energy. As we go down in a group in the periodic table, the size and bond length increases and the bond energy decreases. So, selenium and tellurium will have the least bond energy. Oxygen also has less bond energy due to inter electronic repulsions. So, $S - S$ bond will have the highest energy.
Therefore, option C is the correct answer.

Note:
In the case of $S - S$, the size is lower, so there will be less electron-electron repulsion. This means it will have high bond energy. Also sulphur forms a stronger covalent bond than selenium and tellurium.