For the consecutive unimolecular first order reaction `A overset(k_(1))rarr R overset(k_(2))rarr S`, the concentration of component `A`, `C_(A)` at any time `t` is given by

Options

A. `C_ = C_(A_(0))e^((k_(1)+k_(2))t)`
B. `C_(A) = C_(A_(0))e^(-(k_(1)+k_(2))t)`
C. `C_(A) = C_(A_(0))e^(-k_(1)t)`
D. `C_(A) = C_(A_(0))e^(k_(1)t)`

Answer

C

Explanation

Let `C_(A) = [A]` at time `t`
& `C_(AO) = [A_(0)]` at time `t = 0`
Then from Ist order eqn.
`C_(AO) = C_(A).e^(k_(1)t)`
or `C_(A) = C_(0)e^(-kt)`