Answer to Question #271245 in Molecular Physics | Thermodynamics for Cheppie

Question

Discuss, giving examples, the significance of the bonding energy (E0).

Answer 1

Bond energy serves a very important purpose in describing the structure and characteristics of a molecule. It can be used to determine which Lewis Dot Structure is most suitable when there are multiple Lewis Dot Structures. Energy is always required to break a bond.

Bond energy is a measure of a chemical bond's strength, meaning that it tells us how likely a pair of atoms is to remain bonded in the presence of energy perturbations. Alternatively, it can be thought of as a measure of the stability gained when two atoms bond to each other, as opposed to their free or unbound states.

For example, for homonuclear diatomic molecules containing a single bond, e.g., H₂ , the bond energy is equal to the dissociation energy of the gaseous molecule into isolated atoms. Experimentally it is found that the bond energy between unlike atoms is greater than the energy expected for a truly covalent bond, i.e., one formed by the equal sharing of the bonding electrons between like atoms. The additional bond energy means a more stable bond and is sometimes referred to as the ionic resonance energy.