Chemical Reaction
A chemical change or chemical reaction is the change that matter forms one or more new substances. In a chemical reaction, atoms rearrange to produce new substances. For example, Burning cooking gas (liquid petroleum gas) is a chemical reaction. The gas containing hydrogen (H) and carbon (C) atoms reacts with oxygen gas (O) in air to produce substances mainly carbon dioxide and water vapor. Substances that undergo the chemical reaction are called reactants. New substances that forms are the products. In this example, the reactants are methane gas (C and H atoms) and oxygen gas (O). The products are carbon dioxide (CO) and water vapor (HO).