The bond dissociation energy varies depending on the type of covalent bond.

Covalent bonds are formed when two atoms share electrons. The strength of the bond depends on the distance between the two atoms and the number of electrons they share. The bond dissociation energy is the amount of energy required to break a bond and separate the atoms.

For example, the bond dissociation energy of the H-H bond in hydrogen gas is 436 kJ/mol. This means that 436 kJ of energy is required to break the bond and separate the two hydrogen atoms.

The bond dissociation energy of the O-H bond in water is 464 kJ/mol. This bond is stronger than the H-H bond because oxygen is more electronegative than hydrogen, which means it attracts electrons more strongly. This causes the electrons in the O-H bond to be pulled closer to the oxygen atom, making the bond stronger.

The bond dissociation energy of the C-H bond in methane is 435 kJ/mol. This bond is weaker than the O-H bond in water because carbon is less electronegative than oxygen, which means it attracts electrons less strongly. This causes the electrons in the C-H bond to be further away from the carbon atom, making the bond weaker.

In summary, the bond dissociation energy varies depending on the type of covalent bond. The strength of the bond is determined by the distance between the atoms and the number of electrons they share.


A Level

Need help understanding bond dissociation energy of covalent bonds? Expert tutors answering your Chemistry questions!