Chemistry | MHT CET 2016 | Discussion Page

The rate constant and half-life of a first order reaction are related to each other as

$t_{1/2}=\frac{0.693}{k}$

$t_{1/2}=0.693 k$

C) k=

$0.693 t_{1/2}$

$k t_{1/2}=\frac{1}{0.693}$

Option A

For first order reaction, $k=\frac{2.303}{t}\log\frac{[A_{0}]}{[A]}$

At $t= t_{1/2}$ ,[A]= $[A_{0}]$ /2

$k=\frac{2.303}{t_{1/2}}\log\frac{[A_{}]}{[A_{0}]/2};k=\frac{2.303}{t_{1/2}}\log 2$

$k=\frac{2.303}{t_{1/2}}$ or $t_{1/2}=\frac{0.693}{k}$

Discussion Forum