Question

Based on your understanding, is a combustion reaction endothermic or exothermic? How canyou tell? Where does the energy come from and where does it go to?

Answer 1

A combustion reaction is exothermic because is a chemical reaction in which less energy is needed to break bonds in the reactants than is released when new bonds form in the products. During an exothermic reaction, energy is constantly given off, often in the form of heat. The energy (heat) comes from the energy stored in the chemical bonds of the reactant molecules; which is greater than the energy stored in the chemical bonds of product molecules. The excess energy is generally released to the surroundings when the reaction occurs.