The value of rate constant for a first order reaction is 2.303 `xx10^(-2) sec^(-1)` . What will be time required to reduce the concentration to ` (1)/(10)` th of its initial concentration ?

Options

A. 100 s
B. 10 s
C. 2303 s
D. 230.3 s

Answer

A

Explanation

Let, intial concentration ba a
Then, final concentration (a-x)
`=(1)/(10)`of a
`(a)/(10)`
Integrated rate law experession for first order reaction is
`k=(2.303)/(t)log"(a)/(a-x)`
`or" "t=(2.303)/(k)log"(a)/(a-x)`
`t=(2.303)/(2.303xx10^(-2))log"(a)/(a/10)=10^(2)log"10=10^(2)=100s`