The reaction X → product follows first order kinetics. In 40 minutes, the concentration of X changes from 0.1 M to 0.025 M, then the rate of reaction when concentration of X is 0.01 M is

Step-by-step solution

k = 2.303 t log C 0 C t = 2.303 40 log 0.1 0.025 = 2.303 40 l o g 4 = 2.303 × 0.6021 40 m i n - 1 R a t e = k A = 2.303 × 0.6021 40 m i n - 1 × 0.01 M = 3.47 × 1 0 - 4 M / m i n