Chemists use symbols and formulae to represent elements and compounds. Word equations and balanced chemical equations represent the changes that happen in chemical reactions.
A word equationAn equation in which only the names of the reactants and products are used to model a reaction. represents a chemical reaction using the names of the substances involved. Word equations do not show any chemical symbols or formulae.
Reactants and products
reactantA substance that reacts together with another substance to form products during a chemical reaction. are substances that react together in a chemical reaction. In a chemical reaction, the atomThe smallest part of an element that can exist. or ionElectrically charged particle, formed when an atom or molecule gains or loses electrons. in reactants separate from one another. They join back together in a different way to form productA substance formed in a chemical reaction..
Word equations always take this form:
reactants → products
A + sign separates two or more reactants, or two or more products.
Example word equations
Potassium hydroxide reacts with sulfuric acid. Potassium sulfate and water are formed in the reaction. This means that:
the reactants are potassium hydroxide and sulfuric acid
the products are potassium sulfate and water
the word equation is: potassium hydroxide + sulfuric acid → potassium sulfate + water
There can be different numbers of reactants and products. For example: