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gfd43tg
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Homework Statement
The rate law for the reaction
is found from experiment to be
Suggest a mechanism consistent with the rate law.
Homework Equations
The Attempt at a Solution
Here is the webpage with the solution
http://www.umich.edu/~elements/07chap/frames.htm
Here is the solution
Rate Laws
Relative Rates
Net Rates: Rate of Formation of Product
Need to find an expression for CA* because we cannot easily measure the concentration of A*, use PSSH to solve for CA*.
Solving for CA*
Substituting for CA* in Equation (4) the rate of formation of B is
Relative rates overall
My question is, why do they go about finding the rate law for B from the original reaction, instead of by steps. The way I thought to do this was to find ##r_{A}## from the elementary steps, exactly the same way they found ##r_{A^{*}}##.
##r_{1A} = -k_{1}C_{A}^2##
##r_{2A} = -k_{2}C_{A}C_{A^*}##
##r_{A} = r_{1A} + r_{2A}##
However, there is some complication with ##r_{A2}##. Since the reaction is ##A^* + A \rightarrow A + A##, How can I do the reaction rate of A assuming irreversible? I don't know if it should be ##r_{A2} = -k_{2}C_{A}C_{A^*}## or ##r_{A2} = -k_{2}C_{A}C_{A^*} + k_{2}C_{A}^2##
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