Question

The rate constant of a reaction is 0.01s-1, how much time does it take for 2.4 mol L-1 concentration of reactant reduced to 0.3 mol L-1?

• A. 108.3s-1
• B. 207.9s-1
• C. 248.2s-1
• D. 164.8s-1

Answer 1

Answer:

B. 207.9s-1

Given, K = 0.01s-1 t1/2 = 0.693/0.01 t1/2 = 69.3s [R] = [R]0/2n 2n = [R]0/[R] 2n = 2.4/0.3 2n = 8 n = 3 (number of half-lives) For 1 half-life t1/2 = 69.3s For 3 half-life 3t1/2 = 3 x 69.3s = 207.9s.