Ohhh, you're right. If you know the rate determining step then you have experimental data. So then it is correct to assume the coefficient is the exponent to which the concentration is raised, given it is the rate determining step?
I'm reviewing my old chemistry stuff and the textbooks I read just assumes that the rate law equation is based off of the coefficients of the rate-determining step rather than experimental data.
Example:
2A + 3B > 4C
4C + D > 3E
_______________
2A + 3B + D > 3E
If the rate-determing step is...
Thanks for the reply. That part I fully understand. But what is confusing me is why the coefficient is the power (or order) the concentration is raised to in the rate equation.
When determining a rate law equation you find the individual orders via experimental data, thus you don't assume the coefficients in front of the reactants are their order in the rate law equation. aA + bB -> cC | Rate law equation is not necessarily, rate = k[A]^a[B]^b
But how come when given...
Yea, I completely agree. The worse part is this is an official PCAT practice, and they say 80% of the questions were on old exams so I'd be screwed if it was on the real test. Are there any good general rules I can use to find variance by just look at a set of data or graph.
I'm studying for the PCAT and have come across a few variance questions. I feel like they are just oversimplying the heck out variance. I'll post one of the latest questions ...
[PLAIN]http://img825.imageshack.us/img825/1875/32561537.jpg
The explanation they give is because Class A has...
Considering I am voluntarily doing the problems, its not work I'm trying to have other people do for me. Like I said even one clear, not beating around the bush, answer would have helped. I didn't have time explain everything I knew about the questions b/c I was studying.
Don't worry, a mod can close or delete this thread. Apparently it was too much to request. Next time I'll take pictures of my dry erase board and post them.
I'm not trying to be rude, but I just need explanations on how I should do those questions. I've done all the others questions, but I got stuck on those.