Reactant
noun · Chemistry
Definition
A substance that is present at the start of a chemical reaction and is changed by it.
Explanation
Reactants are written on the left of a chemical equation.
Example
In burning methane, methane and oxygen are the reactants.
Common confusion
Reactants are used up; products are made.
Related terms
- ProductA substance formed in a chemical reaction.
- Chemical equationA representation of a chemical reaction using formulas.
Study guides that use this term
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