Answer:
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