
Rate Laws
For each of the following, determine the rate law of the reaction and find the value of the rate constant (k) with proper units.
1) 2 O_{3 }3 O_{2}












First, set up a generic rate law:
rate = k[A]^{X}Next, create a ratio with the rate laws for 2 experiments:
Simplify and solve for x:
The reaction is first order with respect to [O_{3}] because the exponent was calculated to be 1.
Now we can write the rate law and solve for k by plugging in values for the rate and the [O_{3}] from a single experiment:
2) N_{2}O_{4}2 NO_{2}












3) Xe + 3 F_{2}XeF_{6}
























The rate law includes the concentrations of all the reactants:
rate = k[Xe]^{X}[F_{2}]^{Y}Therefore, we must solve for both X and Y separately.
First choose two experiments in which the initial [F_{2}] are the same and set up a ratio with these experiments:
The [F_{2}] cancel each other out ,and the equation simplifies to find that X = 2. The reaction is second order with respect to [Xe].
Next, we do the same to solve for Y. Choose two experiments in which the initial [Xe] are the same and set up a ratio.
The [Xe] cancel each other out, and the equation simplifies to find that Y = 1. The reaction is first order with respect to [F_{2}].
Now we can write the rate law:
* The reaction is first order with respect to F_{2} and second order with respect to Xe.
Now we have to solve for k:
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