What is order of reaction

Sum of powers of the concentration of terms expressed in rate law is called order of reaction.

Sum of powers of the concentration of terms expressed in rate law is called order of reaction In chemical kinetics, the order of reaction with respect to a given substance (such as reactant, catalyst or product) is defined as the index, or exponent, to which its concentration term in the rate equation is raised.

In chemical kinetics, the order of reaction with respect to a given substance (such as reactant, catalyst or product) is defined as the index, or exponent, to which its concentration term in the rate equation is raised.^[1] For the typical rate equation of form , where [A], [B], ... are concentrations, the reaction orders (or partial reaction orders) are x for substance A, y for substance B, etc. The overall reaction order is the sum x + y + .... For many reactions, the reaction orders are not equal to the stoechiometric coefficients.