Chemistry

Units of Rate Constants

Units of Rate Constants

Units of Rate Constants

The units of rate constants are derived from the rate equation and depend on the order of the reaction. In chemical kinetics a reaction rate constant or reaction rate coefficient, k, quantifies the rate of a chemical reaction. Thus considering time in second the units of ‘k’ are given in the Table below:

Table: Units of the rate constants

In some reactions, the rate is apparently independent of the reactant concentration. The rates of these zero-order reactions do not vary with increasing nor decreasing reactants concentrations. A first order reaction depends on the concentration of only one reactant (a unimolecular reaction). Other reactants can be present, but each will be zero order. A second order reaction is a type of chemical reaction that depends on the concentrations of one second order reactant or on two first order reactants.