(a)
Interpretation:
The rate law for the given mechanism has to be determined.
The reaction:
The accepted mechanism:
Concept Introduction:
Steady-state approximation:
Once the steady state condition is reached, the rate of formation of the intermediate is equal to the rate of destruction of the intermediate.
(a)
Explanation of Solution
The reaction:
The accepted mechanism:
The rate determining step is the slowest step in the mechanism. Thus, the rate of the reaction is given below.
Applying the steady-state approximation on the intermediate
At steady state condition, the rate of formation of the intermediate is equal to the rate of destruction of the intermediate.
Now,
Because the rate of step
Now, the rate law can be modified as given below.
Therefore, the rate law of the reaction is
(b)
Interpretation:
Another mechanism that agrees with the same rate law has to be suggested.
Concept Introduction:
Refer to part (a).
(b)
Explanation of Solution
Another mechanism that agrees with the same rate law is given below.
The imaginary mechanism:
The rate determining step is the slowest step in the mechanism. Thus, the rate of the reaction is given below.
Applying the steady-state approximation on the intermediate
At steady state condition, the rate of formation of the intermediate is equal to the rate of destruction of the intermediate.
Now,
Because the rate of step
Now, the rate law can be modified as given below.
Therefore, the rate law of the reaction is
(c)
Interpretation:
Another mechanism that does not agree with the same rate law has to be suggested.
(c)
Explanation of Solution
Another mechanism that does not agree with the same rate law is given below.
The imaginary mechanism:
The rate determining step is the slowest step in the mechanism. Thus, the rate of the reaction is given below.
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Chapter 11 Solutions
Chemistry: The Molecular Science
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