[velinos]

For the reaction:

4NO2(g) + O2(g) → 2N2O5(g)

d[NO2]/dt = -7.6×10-3 M/s at a particular temperature and set of concentrations.

What are d[N2O5]/dt and d[O2]/dt?
d[N2O5]/dt = .0038 M/s
d[O2]/dt = -.0019 M/s

What is the rate of the reaction?

Rate of reaction: -.0019 M/s

For this I divided (-7.6e-3)/2 since the stoichiometry to N2O5 is:
2 mol N2O5/4 Mol NO2 = 1/2 mol N2O5.
I get .0038 M/s (POSITIVE, since it is forming a product).

As for O2, I think that I should not have to divide by 4? But from the looks of stoichiometry, there is 4 mol of NO2 in 1 mol of O2, so I divided.

I was told, for the rate of reaction, to simply take the smallest number of the two changes and that would be the rate.

If anyone can point me in the right direction, it would be helpful.

Thanks!

[oxygenfluid]

Hello velinos,

I really can't understand the question, but i can say all the math you've done is right. The O2 flow is right and is correct that you divided it by 4 of the concentration of NO2, since its the know one, so all is correct in my point of view.

[velinos]

Thanks for the reply.
The calculation was correct, I just wrote it down incorrectly for some odd reason.