Hello candidate,

Covalent bonding is a very strong kind of chemical bond apart from ionic bonds which are formed by by the donation and acceptance of electrons. In covalent bonding, the electrons of of both the participating atoms get paired with the electrons to form a bond.

The cleavage of chemical bond is generally done by the process of heating the molecules up to their bond dissociation energy, which involves a huge amount of exothermic heat generation.

Hope it helps!!