Revision: Chemical Kinetics JEE Main Chemical Kinetics

The rate of chemical reaction is defined as the change in concentration of reactant or product per unit time.

The rate of a chemical reaction may be defined as the change in concentration of any of the reactants or any of the products per unit time. Thus,

`"Rate of reaction" = "(Change in concentration of a reactant or a product)"/"Time taken for the change"`

Zero order reaction is the reaction whose rate is independent of the reactant concentration and remains constant throughout the course of the reaction.

The reactions that have higher order true rate law but are found to behave as first order are called pseudo first order reactions.

\[\ce{CH3COOCH3 + H2O - CH3COOH + CH3OH}\]

The time in which concentration of reactant becomes half of its initial concentration is called half Life. It is denoted by `t_(1/2)`.

A chemical reaction in which the rate of reaction depends solely linearly on the concentration of one ingredient is referred to as a first-order reaction.

A first-order reaction is a reaction whose rate depends upon the first power of the concentration of reactants, i.e., the rate is directly proportional to the concentration of reactants.

Half life of a reaction is defined as the time required for the reactant concentration to reach one half of its initial value.

Activation energy is the lowest energy necessary to commence a chemical reaction by disrupting the bonds of reactant molecules and creating the activated complex or transition state. It signifies the energy threshold that must be surmounted for a reaction to transpire. Activation energy is typically represented as E_a.

Activation energy may be defined as the excess energy that the reactant molecules (having energy less than the threshold energy) must acquire in order to cross the energy barrier and to change into the products.