Chemical Kinematics

Chemical kinetics, also known as reaction kinematics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is to be contrasted with thermodynamics, which deals with the direction in which a process occurs but in itself tells nothing about its rate. Chemical kinetics includes investigations of how experimental conditions influence the speed of a chemical reaction and yield information about the reaction mechanism and transition states as well as the construction of mathematical modes that also can describe the characteristics of a chemical reaction.

The brain of chemistry deals with the study of the rate of a chemical reaction and the mechanism by which the reaction proceeds are called chemical kinematics.

Concept of Rate of Chemical Reaction

The rate of a chemical reaction is defined as the change in concentration of reactant or product with

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It is measured in molelitr–S–

Lets us consider the following types of chemical reactions

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Here ‘-sign’ indicates that a decrease in concentration at A with respect in time, while ‘+’ sign indicates the increase in the concentration of ‘B’ with respect to time.

Types of Rates of Chemical Reactions

There are three types of rate of chemical reaction

1. The average rate of chemical reaction
2. Instantaneous rate of chemical reaction

• Equivalent rate of chemical reaction

1. Average Rate of Chemical Reaction

The rate of a chemical reaction due to the change in concentration of reactant or product over a specific interval of time is called the average rate of a chemical reaction. It is denoted by av.

Lets us consider the following type of chemical reaction

C→D

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1. Instantaneous Rate of Chemical Reaction
   The rate of chemical reaction for a particular instant of time is called the instantaneous rate of a chemical reaction. It is denoted by ri.
2. Equivalent Rate of Chemical ReactionThe rate of chemical reaction for which 1 mole of each reactant and product is called the equivalent.

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