Integrated Rate Law

Question

The gas phase decomposition of hydrogen peroxide at 400 °C

H₂O₂(g)H₂O(g) + ½ O₂(g)

is second order in H₂O₂.

In one experiment, when the initial concentration of H₂O₂ was 8.60×10^-2 M, the concentration of H₂O₂ dropped to 1.26×10^-2 M after 77.1 seconds had passed.

Based on these data, the rate constant for the reaction is _________M^-1 s^-1.

Please include the answer.

Answer 1

Second order integrated rate law: 1/[A] = 1/[A]_o + kt

[A] = 1.26x10^-2 M

[A]o = 8.60x10^-2 M

k = ?

t = 77.1 s

1/1.26x10^-2 = 1/8.60x10^-2 + 77.1 k

79.37 - 11.63 = 77.1k

67.74 = 77.1k

k = 0.979 M^-1s^-1