Comparison between exothermic reaction and endothermic reaction

1. Thermochemistry
Exothermic Reaction Endothermic Reaction
 Is a reaction that release  Is a reaction that absorb
heat to the surrounding heat from the surrounding
 Temperature of the  Temperature of the
surrounding increase surrounding decrease
 Energy level diagram  Energy level diagram
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2. Thermochemistry
Exothermic Reaction Endothermic Reaction
 Energy of the products is  Energy of the products is
less than reactants. more than reactants.
 ∆H = negative  ∆H = positive
 Energy for bond breaking is  Energy for bond breaking is
less than energy from bond more than energy from
formation bond formation
 More energy released  More energy absorbed for
during bond formation than bond breaking than energy
energy absorbed for bond released during bond
breaking formation
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3. Thermochemistry
Exothermic Reaction Endothermic Reaction
 Examples:  Examples:
 Neutralization reaction  Photosynthesis
 Reaction between acids and  Dissolving ammonium salts in
metals water
 Adding water to concentrated  Decomposition of metal
acids carbonate
 Reaction between reactive  Decomposition of metal
metals with water nitrates
 Respiration
 Burning of fuels
 Haber process
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