Question

A chemistry student needs to calculate the rate constant (k) for the following first-order reaction based on the given data: The half-life of the reaction is 20 seconds when the initial concentration of reactant is 0.2M. What is the rate constant of the reaction?

Answer 1

To calculate the rate constant  k  for a first-order reaction, we can use the formula for the half-life of a first-order reaction:t½ = 0.693 / kwhere t½ is the half-life of the reaction and k is the rate constant.We are given the half-life  t½  as 20 seconds, and we need to find the rate constant  k . We can rearrange the formula to solve for k:k = 0.693 / t½Now, we can plug in the given half-life:k = 0.693 / 20 sk  0.03465 sThe rate constant  k  for the reaction is approximately 0.03465 s.