What is chemical kinetics?
Chemical kinetics is the study of measures the rate of reaction process under conditions such as temperature, pressure and concentration of a solution.
What is the importance of chemical kinetics?
The study of chemical kinetics helps determine the rate of reaction and understand the mechanism of the number of chemical reactions. The experimental data is helpful in the development of modern theories of the chemical reactivity of molecules.
RATE OF REACTION
What is the rate of reaction?
The concentration of reactant is converted into the concentration of product is called the rate of reaction.
Consider the simple reaction of the type,
A → P
Starting the reaction rate depends upon the concentration of reactant A. As the reaction proceeds, the reactant (A) concentration decreases with time; the rate of reaction at given by the expression,
Here,
-dcA = small decrease in the concentration of A in a small interval of time dt
cA = concentration of the reactant A at a given instant
K = rate constant
The concentration of product P increases with time, and the rate of reaction expressed in terms,
dcP = small increases the concentration of product P at a small interval of time dt
From equations (1) and (2),
For the reaction of type,
A +B → C + D,
The rate of reaction is expressed as,
RATE LAW AND RATE CONSTANT
The rate of reaction;
A → Product
Experimentally given by,
Here, k= rate constant of reaction at a given temperature
If concentration A is one, then
cA = 1 and the r = k
For general reaction,
The rate law expression gives the rate of reaction,
If cA =cB = cC then k =r
The general rate constant of a reaction is defined as the rate of reaction when the concentration of each reactant is unity.
