The rate constant for a first order reaction is `4.606 times 10^(-3)s^(-1)`. The time required to reduce 2.0 g of the reactant to 0.2 g is

Options

A. 100 s
B. 200 s
C. 500 s
D. 1000 s

Answer

C

Explanation

For a first order reaction,
`k=(2.303)/tlog""[R]_(0)/([R])`
`rArr t=(2.303)/(4.606 times 10^(-3) s^(-1))log(2/(0.2))=(2.303 times 10^(3))/(4.606)=500s`