Law of Conservation of Mass: A principle stating that mass is neither created nor destroyed in a chemical reaction; the mass of the reactants equals the mass of the products. Catalyst: A substance tha...Law of Conservation of Mass: A principle stating that mass is neither created nor destroyed in a chemical reaction; the mass of the reactants equals the mass of the products. Catalyst: A substance that increases the rate of a chemical reaction without being consumed in the process, by lowering the activation energy. Combustion Reaction: A chemical reaction in which a substance combines with oxygen, releasing energy in the form of heat and light, and producing carbon dioxide and water (usually).
