Chemistry - Exothermic and endothermic reactions
Exothermic and endothermic reactions
In understanding why some chemical reactions release energy as heat while
others need a continual supply of heat energy to keep proceeding, we
reflect again on the fundamental ideas of chemical reactions, namely
bond-breaking and bond-making.
The overall energy (heat) change accompanying a chemical reaction reflects
the difference between that required for bond-breaking (in the reactants)
and that released during bond-making (in the products).
If more energy is required to break bonds (i.e. for the reactants to
react) than is released during bond-making (i.e as the products are formed)
then the energy content of the products is greater than the energy content
of the reactants and the reaction is ENDOTHERMIC.
Previous | Next