Reaction rate: changes in a concentration of a product or a reactant per unit time. Δ[ ] concentration Reaction rate = —— Δ t change [ ] Tangent 1 Tangent 2 Reaction Rate Defined •Non-disruptive techniques •Disruptive techniques: Chemical Analysis MethodReaction rate: changes in a concentration of a product or a reactant per unit time. Δ[ ] concentration Reaction rate = —— Δ t change [ ] Tangent 1 Tangent 2 Reaction Rate Defined •Non-disruptive techniques •Disruptive techniques: Chemical Analysis Method