Energitics

Enerry can neither be create or destroyed but converted from one form to another. All chemical reaction are accomanied by some form of energy change, some are obvious(like burning) but most goes unnoticed. Thermochemistry When a reaction occurs bonds are broken in the reactants and bonds are formed in the products made. Energy must be given in to the system for a reaction anfd energy is given off by the products. This process results in a change in the chemical energy. At the end of the reaction, if energy is given out, the reaction is exothermic. At the end of the reaction, if energy is taken in, the reaction is endothermic.   The amount of energy given off at the end of the reaction depends on the amount of substance used