Question

Question #4035f

Answer 1

The definition for the half goes as "the time period required for concentration to become exactly one half of the initial one"
The Mathematical rate law for 1st order reaction is;

Explanation:

`(dA)/(dt) = k[A]`

OR

`k=(2.303/t ) log [Ao] / [At]`

putting the value of `[At] =[Ao]/2` at `t =t(1/2)`

`k=(2.303/t) log 2`

`k=(2.303/t) 0.3010`

`k =0.693/(t(1/2))`

Similarly in general

`t(1/2)` is directly proportional to `(1/[Ao])^(n - 1)`

so for 2nd order reaction it will be
`t(1/2)` will be directly proportional to `1/[Ao]`