Final answer:
A chemical reaction is the process of transforming reactants into products through the breaking and formation of chemical bonds. Chemical equations represent these reactions and exemplify the conservation of mass. An example of a chemical reaction is the burning of methane, where methane and oxygen react to form carbon dioxide and water.
Step-by-step explanation:
What Is a Chemical Reaction?
A chemical reaction is a process that changes some chemical substances into others, involving the breaking and formation of chemical bonds between atoms. The reactants are the substances that start a chemical reaction and are found on the left side of a chemical equation. The products are the new substances that form as a result of the reaction and are found on the right side of a chemical equation. For example, when methane (CH4) burns in the presence of oxygen (O2), it forms carbon dioxide (CO2) and water (H2O).
Reactants and Products
Reactants are substances that undergo change during the chemical reaction. Products are the new substances that are formed. The process of a chemical reaction involves the breaking of bonds in the reactants and the formation of new bonds in the products. Bonds break because energy is supplied to the reactants. This energy, known as activation energy, is necessary to initiate the reaction. Chemical reactions can be either endergonic, which absorb energy, or exergonic, which release energy. The formation of water from hydrogen and oxygen is an example of an exergonic reaction.
Writing a Chemical Equation
A chemical equation is a symbolic representation of a chemical reaction. It shows the reactants transforming into the products, while illustrating the conservation of matter. An example is the formation of water from hydrogen and oxygen, expressed as 2H2+ O2 -> 2H2O.