- The rate of reaction changes from time to time as the reaction happens.
- The rate of reaction at a particular time is called the instantaneous rate.
- The instantaneous rate of a reaction is equal to the gradient of tangent at a particular time.
Rate of reaction = Δ(product) Δ(Time) Δ(Product) = Change of the amount of product Δ(Time) = Change of the time
Example
The graph shows the volume of carbon dioxide gas released over time in a chemical reaction. Find the rate of reaction at t = 40s.
Answer:
Rate of reaction at 40s = gradient of the tangent at 40s
Rate of reaction = 132-48 70-10 =1.4c m 3 s -1