The document discusses endothermic and exothermic reactions in relation to bond formation and breaking. It provides examples of reactions that absorb (endothermic) or release (exothermic) heat. The key information is that bond FG in reaction 4 is more stable than bond EB in reaction 3 because breaking the FG bond requires 300kJ more energy, meaning it takes more energy to break and is thus more stable.

1. BONDING cont…
By Monique Gordon
Energy of Bonding:
Endothermic –
Reaction 1(endo): CD + 100kJ C+D
• heat is a reactant
• heat is absorbed Reaction 2 (exo): A + B AB + 100kJ
• breaking a bond
Reaction 3: E + B EB + 100kJ
Exothermic –
Reaction 4: F + G FG + 400kJ
• heat is a product Which bond is more stable, EB or FG?
FG, because it takes more energy (300kj more) to
• heat is released break the bond than EB.
• making a bond
• less potential energy
• bond is more stable
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