3. examine the reaction mechanism found below:\na + b₂ → ab₂ (slow)\nab₂ + c → ab₂c (fast)\nab₂c + c → b₂c₂…
3. examine the reaction mechanism found below:\na + b₂ → ab₂ (slow)\nab₂ + c → ab₂c (fast)\nab₂c + c → b₂c₂ + a (fast)\nb₂c₂ → d + e (fast)\noverall equation:\n\na. draw a circle around any reaction intermediates.\nb. draw a box around any species that can be considered a catalyst.\nc. in the box above, provide the overall equation for this process.\nd. in the box below, provide the rate law based on this mechanism.\nrate law:\n
Answer
Explanation:
Step1: Identify reaction intermediates
Reaction intermediates are species that are formed in one step and consumed in a subsequent step. In the given mechanism, (AB_{2}), (AB_{2}C), and (B_{2}C_{2}) are formed in one step and consumed in another.
Step2: Identify catalyst
A catalyst is a species that is consumed in an early step and regenerated in a later step. In the given mechanism, (A) is consumed in the first step and regenerated in the third step.
Step3: Determine overall equation
Add all the steps together and cancel out the intermediates ((AB_{2}), (AB_{2}C), (B_{2}C_{2})) and the catalyst ((A)): $$ \begin{align*} A + B_{2}&\to AB_{2}\quad(\text{slow})\ AB_{2}+C&\to AB_{2}C\quad(\text{fast})\ AB_{2}C + C&\to B_{2}C_{2}+A\quad(\text{fast})\ B_{2}C_{2}&\to D + E\quad(\text{fast})\ \hline 2C + B_{2}&\to D + E \end{align*} $$
Step4: Determine rate law
The rate - determining step is the slow step. The rate law is based on the reactants of the slow step. The slow step is (A + B_{2}\to AB_{2}). So the rate law is (rate = k[A][B_{2}])
Answer:
a. Reaction intermediates: (AB_{2}), (AB_{2}C), (B_{2}C_{2}) b. Catalyst: (A) c. Overall equation: (2C + B_{2}\to D + E) d. Rate law: (rate = k[A][B_{2}])