C7.4 bond energy calculations

• In chemical reactions, energy must be supplied to break the bonds between atoms and reactants
• When new bonds are formed between atoms in a chemical reaction, energy is released
• in an exothermic reaction, the energy released when new bonds are formed is greater than the energy required to break them
• in an endothermic reation, the energy released when new bonds are formed is less than the energy required to break them
• you can calculate the overal energy change in a chemical reactions using bond energies

Bond energy - the energy required to break a specific chemical bond