The following reaction is second order in [A] and the rate constant is 0.039 M^-¹s^-¹:
A - B
The concentration of A was 0.30 M at 23s. The initial concentration of A was _ M.

Question

The following reaction is second order in [A] and the rate constant is 0.039 M^-¹s^-¹: A - B The concentration of A was 0.30 M at 23s. The initial concentration of A was _ M.

Quizplus · Accepted Answer

The integrated rate law for a second order reaction is:

1/[A]t - 1/[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.

Plugging in the given values:

1/0.30 - 1/[A]0 = (0.039 M^-1 s^-1)(23 s)
1/[A]0 = 0.41 M

Therefore, the initial concentration of A was 0.41 M.

The Following Reaction Is Second Order in [A] and the Rate