For the reaction of nitric oxide, NO with chlorine Cl2
2NO(g) + Cl2(g)--> 2NOCl(g)
the observed rate law is
k[NO]^2 [Cl2]
what is the reaction order with respect to nirtic oxide? with respect to Cl2? What is the overal order?
how
You go with the superscripts. Second order with respect to NO (because of the squared term), first order with respect to Cl2 (to the first power) and third order over all (2+1 = 3).
To determine the reaction order with respect to nitric oxide (NO) and chlorine (Cl2), as well as the overall order of the reaction, you can use the method called the "Method of Initial Rates."
Here's how to find the reaction order with respect to NO:
1. Select two experiments with different initial concentrations of NO but the same concentration of Cl2.
For example, let's say Experiment 1 has [NO]1 and Experiment 2 has [NO]2.
2. Measure the initial rates of the reactions in both experiments and denote them as Rate1 and Rate2, respectively.
3. Since the observed rate law is given as k[NO]^2 [Cl2], we can set up the following ratio of initial rates:
(Rate1/Rate2) = ([NO]1^2 [Cl2])/([NO]2^2 [Cl2])
4. Cancel out the [Cl2] terms since they are the same in both experiments:
(Rate1/Rate2) = ([NO]1^2)/([NO]2^2)
5. Solve the equation for the ratio of initial concentrations of NO:
([NO]1^2)/([NO]2^2) = (Rate1/Rate2)
Taking the square root of both sides, we get:
[NO]1/[NO]2 = sqrt(Rate1/Rate2)
6. Calculate the ratio of initial concentrations of NO by dividing their values:
[NO]1/[NO]2 = sqrt(Rate1/Rate2)
7. The resulting ratio will give you the reaction order with respect to NO.
If the ratio is different from 1, then the reaction is not first order with respect to NO. The ratio will indicate the order, such as 2 for second order.
Follow the same steps to determine the reaction order with respect to Cl2 and finally calculate the overall reaction order by adding the individual orders you obtained for each reactant. In this case, the overall reaction order will be the sum of the Orders with respect to NO and Cl2.