And, an expression for a half-life of zero-order reaction's rate constant is given by, The half-life of a zero-order reaction is explained below on how it is derived, including the expression.įor the half-life of zero-order reaction, the units of the rate constant are mol.L -1. K is the rate constant of the reaction (unit - M (1-n) s -1, where ‘n’ is the order of reaction)ĭerivation of Half-Life Formula for Zero-Order Reaction is the initial reactant concentration (unit - mol.L-1 or M), and T 1/2 is the half-life of certain reaction (unit - seconds) The mathematical expression can be employed to determine the half-life for a zero-order reaction is, t 1/2 = 0 /2kįor the first-order reaction, the half-life is defined as t 1/2 = 0.693/kĪnd, for the second-order reaction, the formula for the half-life of the reaction is given by, 1/k 0 The half-life formula for various reactions is given below. It is essential to note that the half-life formula of a reaction varies with the reaction's order. It is essential to make note that the half-life is varied between different types of reactions. The concepts of half-life play a vital role in the administration of drugs into the target, especially in the elimination phase, where half-life is used to discover how quickly a drug decrease in the target once it has been absorbed in a period of time (sec, minute, day) or the elimination rate constant ke (minute -1, hour -1, day -1 ). The half-life application is used in chemistry and in medicine to predict the concentration of a substance over time. The half-life chemistry or a half-life of a reaction, t 1/2, is defined as the specific amount of time required for a reactant concentration to decrease by half when compared to its initial concentration.

Half life decay walkthrough