Question

Briefly explain why the use of initial rate in chemical kinetics gives a chemist more information than the average rate.

Answer 1

initial rate in chemical kinetics gives a chemist more information because

We calculate the average rate of a reaction over a time interval by dividing the change in concentration over that time period by the time interval. For the change in concentration of a reactant, the equation, where the brackets mean "concentration of", is

  

rate = - [ reactant at t₂ ]  - [ reactant at t₁ ] / t₂ -t ₁

see here we need 4 varibles to define rate while

r = k [A]^a [B]^b

The initial concentrations of A and B are known; therefore, if the initial reaction rate is measured, the only unknowns in the rate law are the rate constant, k, and the exponents a and b. One typically measures the initial rate for several different sets of concentrations and then compares the initial rates. this method is used irrespective of no of reaction taking place

initial rate is very useful because we can find rate as well as order of reaction , rate constant , t_1/2we can also plot graph with many combination like rate vs tims, concerntation vs time which are very much useful for chemist etc .

which are cannot find by average rate.