At 25°C the rate constant for the first-order decomposition of a pesticide solution is 6.40 × 10^-3 min-1.If the starting concentration of pesticide is 0.0314 M,what concentration will remain after 62.0 min at 25°C?

Question

Quizplus · Accepted Answer

We can use the first-order integrated rate law to solve for the remaining concentration:

ln([A]t/[A]0) = -kt

where [A]t is the concentration at time t, [A]0 is the initial concentration, k is the rate constant, and t is time.

We can rearrange this equation to solve for [A]t:

[A]t = [A]0 * e^(-kt)

Substituting the given values:

[A]t = (0.0314 M) * e^(-6.40 × 10^-3 min^-1 * 62.0 min)

[A]t = 2.11 × 10^-2 M

Therefore, the concentration that will remain after 62.0 min is 2.11 × 10^-2 M. The correct answer is D.

At 25°C the Rate Constant for the First-Order Decomposition of a Pesticide