Final answer:
The rate of a chemical reaction is the speed at which reactants change to products over a given time. It is determined by measuring the change in amount of reactants or products per unit time.
Step-by-step explanation:
The rate of a chemical reaction refers to the speed at which reactants change to products over a given time. It is the change in the amount of a reactant or product per unit time.
For example, if a reactant is being consumed and a product is being formed, the rate of reaction will be determined by how quickly the reactant is being used up or how quickly the product is being produced.
Rate of reaction can be measured by various methods depending on the nature of the reaction, such as changes in volume or pressure for gaseous reactions, light absorption for reactions involving colored substances, or changes in conductivity for reactions involving aqueous electrolytes.