The units of a rate constant for zero, first and second order reactions are given in the textbook. If the time units are minutes, what would you expect the units to be for a third order reaction?
a. 1/min3 b. mol2/L2-min c. L/mol-min2 d. L2/mol2-min e. L2/mol2-min2
help help!
chemistry - DrBob222, Friday, February 17, 2012 at 10:25pm
rate laws:
zero order is rate = k so units are M/s or moles/l*s
1st order is rate = k*(A)
k = rate/(A) = moles/L*ws/(moles/L) = 1/s or s^-1.
Here is a site that will give you the units of zero, 1st, 2nd, and a formula for calculating any order units for k. Just scroll to that part of the site.
guessing B?
You shouldn't guess. You should KNOW. Either I forgot to give you the link that I said I gave you or you didn't look at it. Anyway, here is the link. C-mon. Figure it out.
rate = k(A)^3
k = rate/(A)^3
rate has units of M/min (in this problem) and (A) has units of M so
k = M/min divided by M.
M = moles L. Now the units are k are ??
http://en.wikipedia.org/wiki/Rate_equation
I get L^2/mol^2 -min. Is that correct?
yes
To determine the units for a third order reaction, we should refer to the information given in the textbook. The units for zero order and first order reactions are provided, which are moles per liter per second (mol/L*s) and per second (s^-1) respectively.
To find the units for a second order reaction, we can use the formula provided in the textbook. The formula for calculating the units for any order reaction is not mentioned but can be found in the additional resource provided by DrBob222. We should scroll to that part of the website to find the relevant information.
Based on the information provided, we cannot directly determine the units for a third order reaction. We should follow the instructions given by DrBob222 and refer to the provided resource for the formula to calculate the units for any order reaction.