Question

hi, I would like help with corrections! I recieved my homework back and the teacher circled 6.9 M ^-1 s^-1. How do you reach this answer? How do I apply the formula for second order? : 1/[A] - 1/[A] = kt ( this was just what the formula in my textbook looked like but I know when you google something there is slight variation in each, and each person likes to write there formula a little differently that helps them)

thank you so much :)

17. For a certain overall second-order reaction with the general form aA → products, the initial rate of reaction is 0.50 M-5-1 when the initial concentration of the reactant is 0.27 M. What is the rate constant for this reaction? a. 0.039 M-.5-1 (b. 6.9 M-1.5-1 0.50 M-1.5-2 d. 0.54 M-2.5-1 e. 25 M-1.5-1 3.703 - 2 [A2 -[A] = Ky [27] -Escue = kt

Answer 1

This is 2nd order reaction.

So, the rate law is:

Rate = k [A]^2

Given:

Rate = 0.50 M/s

[A] = 0.27 M

Use:

Rate = k [A]^2

0.50 M/s = k (0.27 M)^2

k = 6.9 M-1.s-1

Answer: b