The rate constant for this second‑order reaction is 0.550 M-1⋅s-1 at 300∘C. A ⟶ productsHow long, in seconds, would it take for the concentration of A to decrease from 0.800 M to 0.380 M?

5.29 seconds

Explanation:

The reaction follows a second-order

Rate = kC^2 = change in concentration/time

k = 0.550 M^-1. s^-1

C = 0.380 M

Co = 0.800 M

Change in concentration = Co - C = 0.8 - 0.38 = 0.42 M

0.55*0.38^2 = 0.42/t

t = 0.42/0.07942 = 5.29 seconds