Consider the following mechanism:
STEP 1: A ---> B +C (slow)
STEP 2: C+D ---> E (fast)
OVERALL: A+D---> B+E
Determine the rate law for the overall reaction (where the overall rate constant is represented as k).
please help me. how do i do this problem?
k[A]
To determine the rate law for the overall reaction, we need to consider the rate-determining step, which is the slower step in the mechanism.
In this case, the rate-determining step is Step 1: A ---> B + C.
The rate of the overall reaction can be expressed as the rate of the rate-determining step, since the rate of the overall reaction depends on the rate of the slowest step.
The rate law for Step 1 can be written as:
Rate = k1[A]
Where k1 is the rate constant for Step 1 and [A] is the concentration of A.
Since the overall reaction involves the consumption of both A and D, and each reactant appears in a different step, we need to consider the concentrations of both A and D in the rate law expression. Therefore, we can express the rate law for the overall reaction as:
Rate = k [A]^m [D]^n
Where k is the overall rate constant, [A] is the concentration of A, [D] is the concentration of D, and m and n are the orders of reaction with respect to A and D, respectively.
In this case, since A is involved only in Step 1 and D is involved only in Step 2, the order of reaction with respect to A is 1 and the order with respect to D is also 1.
Therefore, the rate law for the overall reaction is:
Rate = k [A]^1 [D]^1
Rate = k [A] [D]
I hope this helps! Let me know if you have any further questions.
To determine the rate law for the overall reaction, we need to analyze the individual steps and determine their respective rate laws. The rate law for each step is determined by the reactants' concentrations raised to the power of their respective reaction orders.
In STEP 1: A ---> B + C (slow)
The rate law can be written as: r1 = k1 [A]^x
Since no other reactants are involved in this step, the overall reaction order for STEP 1 is x.
In STEP 2: C + D ---> E (fast)
The rate law can be written as: r2 = k2 [C]^y [D]^z
Since both C and D are involved in this step, the overall reaction order for STEP 2 is y + z.
Now, let's consider the overall reaction: A + D ---> B + E
Since A reacts in STEP 1 and D reacts in STEP 2, the overall reaction order will be the sum of the reaction orders from the individual steps.
Overall reaction order = x + (y + z)
Therefore, the rate law for the overall reaction can be written as:
r = k [A]^x [C]^y [D]^z
Please note that the specific values of x, y, and z are not provided in the question, so it is not possible to determine their exact values without additional information.