Bond Energy

• Is bond breaking endo or exo thermic?

  Endothermic
• Is bond forming exo or endo thermic?

  Exothermic
• In exothermic reactions the energy required for bond breaking is less than energy released in formation.
• In endothermic reactions the energy required for bond breaking is more than energy released in bond formation
• Mean bond enthalpy

  The mean enthalpy change when one mole of gaseous covalent bones is broken over a change of compounds