Question

Given the following data, determine the rate constant of the reaction

2NO(g) + Cl2(g) 2NOCl(g)
Experiment [NO] (M) [Cl2] (M) Rate (M/s)
1 0.0300 0.0100 3.4 x 10–4
2 0.0150 0.0100 8.5 x 10–5
3 0.0150 0.0400 3.4 x 10–4

a. 1.13 M –2s–1
b. 9.44 M –2s–1
c. 37.8 M –2s–1
d. 0.0265 M –2s–1
e. 59.6 M –2s–1

Answer 1

These are difficult to do on this forum but here is how you go about it.
rate = k(NO)^x(Cl2)^y

You want to determine x and y, the exponents, first. Use experiments that have the same concn for each; i.e., if you use 2 and 3 (NO) will cancel and you can determine y. Then use experiments 1 and 2 so (Cl2) cancels and you can determine x. Knowing x and y, then choose any of the 3 experiments, substitute the concns and rate and solve for k. Post your work if you get stuck.

Answer 2

I am getting stuck on this problem. I got x=1 and y=1 when I used experiment 2/1 and then experiment 3/2. However I am unsure what to do next. The formula I'm using is Rate=K(NO)^x(Cl2)^y is this correct? I am getting 37.77 as an answer when I plug in values into experiment 2:
8.5*10^-5=k(.015)^2(.01)

Help would be greatly appreciated!