The bond energy is the energy that must be supplied to break the bond. Ionic substances are held together by strong bonds.
This question is incomplete but I will try to explain what is meant by average bond energy as the tables are missing.
The average bond energy of a bond simply means the energy that is stored in that bond as it holds two atoms together. It is equal to the energy that must be supplied to break the bond. The numerical value of the bond energy can not be deduced as the data is missing.
Learn more about bond energy: https://brainly.com/question/26141360