Answer:
Rate = K[NH4+][NO2–]
Explanation:
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In this case, since rate laws include the concentration of the species contributing to the rate of a chemical reaction; this question asserts this reaction is proportional to the concentration of ammonium (NH4+) and the concentration of nitrogen dioxide (NO2–); therefore, the rate law must contain the concentration of both reactants, for that reason, the answer would be Rate = K[NH4+][NO2–] as it contains the concentration of the aforementioned species.
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