For the elementary reaction

NO 3 + CO → NO2 + CO 2

the molecularity of the reaction is __________, and the rate law is rate = __________.

A) 2, k[NO 2][CO 2]

B) 2, k[NO 3][CO]/[NO2 ][CO 2]

C) 4, k[NO 3][CO][NO 2][CO 2]

D) 4, k[NO 2][CO 2]/[NO 3][CO]

E) 2, k[NO 3][CO]

how do i solve problems like these?

3 answers

I think the secret is the wording. In "elementary" reactions, you go with the coefficients in the balanced equation.
So reactions involving 1 molecule are unimolecular, while two or three or either bimolecular or termolecular. So this is a bimolecular equation and the rate law is k[NO3][CO] so I would go with answer E.

ok thank you!