For a first order reaction, (A) → products, the concentration of A changes from 0.1 M to 0.025 M in 40 minutes. The rate of reaction when the concentration of A is 0.01 M is

- 3.47 x 10
^{-5}M/min - 1.73 x 10
^{-4}M/min - 1.73 x 10
^{-5}M/min - 3.47 x 10
^{-4}M/min

**Answer**

k = 2.303/40*log(0.1/0.025)

k = 0.693/20

For a First order reaction,

rate = k[A]

rate = 0.693*10^{-2}/20

**The correct option is D.**