The rate law for the reaction 2NO2 + O3 → N2O5 + O2 is rate = K[NO2][O3]. Which one of the following mechanisms Is consistent with this rate law?
A. NO2 + NO2 → N2O2 (fast)
N2O4 + O3 → N2O5 + O2 (slow)
B. NO2 + O3 → NO5 (fast)
NO5 + NO5 → N2O5 + (5/2)O2 (slow)
C. NO2 + O3 → NO3 + O2 (slow)
NO3 + NO2 → N2O5 (fast)
D. NO2 + NO2 → N2O2 + O2 (slow)
N2O2 + O3 → N2O5 (fast)

C. NO2 + O3 → NO3 + O2 (slow)

NO3 + NO2 → N2O5 (fast)

Explanation:

A reaction mechanism represents an amount of elementary steps that explain how a reaction proceeds. The mechanism must explain the experimental rate law. Also, the slow step is the rate determining step.

This rate law is obtained from the multiplication of the reactants in the slow step, thus:

A. NO2 + NO2 → N2O2 (fast)

N2O4 + O3 → N2O5 + O2 (slow)

Rate law:

rate = k [N2O4] [O3]

This mechanism is not consistent with rate law.

B. NO2 + O3 → NO5 (fast)

NO5 + NO5 → N2O5 + (5/2)O2 (slow)

Rate law:

rate = k [NO5]²

This mechanism is not consistent with rate law.

C. NO2 + O3 → NO3 + O2 (slow)

NO3 + NO2 → N2O5 (fast)

Rate law:

rate = k [NO2] [O3]

D. NO2 + NO2 → N2O2 + O2 (slow)

N2O2 + O3 → N2O5 (fast)

Rate law:

rate = k [NO2]²

This mechanism is not consistent with rate law.

Thus, right solution is:

C. NO2 + O3 → NO3 + O2 (slow)

NO3 + NO2 → N2O5 (fast)

the answer is na (sodium)

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.