The rate of a first-order reaction is 0.04 mol L s at 10 seconds and 0.03 mol L s at 20 seconds after initiation of the reaction. The half-life period of the reaction is. (NEET 2016)

For a first order reaction CHEMICAL KINETICS 32 1 2 1 2 2.303 log 2.303 0.04 log 20 10 0.03 2.303 0.1249 10 x a x k t t a x k k 1/2 0.693 2.303 0.1249 10 x t 1/2 0.693 10 24.1sec 2.303 0.1249 x x t