Rate of Reaction
Rate of reaction:
• The change in concentration of reactant or product per unit time.
Rate= change in concentration/time=mol dm-1s-1
• The change in volume of gas per unit time.
Rate = change in volume /time=cm3s-1.
• The loss of mass per unit time.
Rate = loss in mass/time=gs-1
• Time taken for product to form.
Rate = constant/time=s-1.
How to calculate rate of reaction from the graph:
In order to take the instantaneous rate from the i.e concentration- time graph take the
tangent. The gradient of the tangent will give the instantaneous rate. While to
calculate the average rate of reaction= total concentration change/total time taken.
Factors affecting the Rate of Reaction:
• Temperature: it is directly proportional to the rate of reaction. Higher the
temperature ,higher the rate of reaction and vice versa as increasing the
temperature will increase the frequency of collisions with higher kinetic
energy thus more successful collisions or vice versa. The energy possessed by
the particles will be more than the activation energy.
, Initially the rate of reaction was more steep as there were more reactants and then the
rate becomes constant.
• Pressure: increasing the pressure will increase the rate of reaction as the
number of particles per unit area increases hence results in more frequent
collisions leading to more successful collisions vice versa.
• Surface area: lesser the particle size lesser the surface area and thus there
would be more frequent collisions among the reactants as more particles are
exposed to reactants hence increasing the rate of reaction. And vice versa.
• Catalysts: increases the rate of reaction by decreasing the activation energy
without being chemically altered at the end of reaction.
Rate of reaction:
• The change in concentration of reactant or product per unit time.
Rate= change in concentration/time=mol dm-1s-1
• The change in volume of gas per unit time.
Rate = change in volume /time=cm3s-1.
• The loss of mass per unit time.
Rate = loss in mass/time=gs-1
• Time taken for product to form.
Rate = constant/time=s-1.
How to calculate rate of reaction from the graph:
In order to take the instantaneous rate from the i.e concentration- time graph take the
tangent. The gradient of the tangent will give the instantaneous rate. While to
calculate the average rate of reaction= total concentration change/total time taken.
Factors affecting the Rate of Reaction:
• Temperature: it is directly proportional to the rate of reaction. Higher the
temperature ,higher the rate of reaction and vice versa as increasing the
temperature will increase the frequency of collisions with higher kinetic
energy thus more successful collisions or vice versa. The energy possessed by
the particles will be more than the activation energy.
, Initially the rate of reaction was more steep as there were more reactants and then the
rate becomes constant.
• Pressure: increasing the pressure will increase the rate of reaction as the
number of particles per unit area increases hence results in more frequent
collisions leading to more successful collisions vice versa.
• Surface area: lesser the particle size lesser the surface area and thus there
would be more frequent collisions among the reactants as more particles are
exposed to reactants hence increasing the rate of reaction. And vice versa.
• Catalysts: increases the rate of reaction by decreasing the activation energy
without being chemically altered at the end of reaction.
