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Rydberg Equation

Posted: Sat Apr 21, 2018 7:50 pm
by Fiona Grant 1I
I remember that in class, we did example where we found the frequency of light being emitted when an electron changes energy levels. In this example, we used the equation E = -hR/n^2 at each energy level and then subtracted them to find the frequency using E = hv. I understand how the Rydberg equation will yield the same answer, but we intentionally avoided using the Rydberg equation and were therefore not given the equation to use in class. However, I noticed that for homework problem 1.15, it is impossible to complete the problem without using the Rydberg equation. I was wondering when we can or should be using the Rydberg equation? Is it preferred that we use the method we did in class to complete these types of problems?

Re: Rydberg Equation

Posted: Sat Apr 21, 2018 7:50 pm
by Natalie Noble 1G
I too am not sure what is expected of us, but just to be safe I would know the equation, since it was needed for a hw problem and we talked about it in our discussion sections. I would just know how to derive it from the equation he did give us in class ( E(n)=-Rh/(n^2) )

E(initial) = E(final)

E(n(initial) = E(n(finial)) + photon

-Rh/(n(initial)^2) = -Rh/(n(finial)^2) + hv

-R/(n(initial)^2) = -R/(n(final)^2) + v

v = -R/(n(initial)^2 + R/(n(final)^2

v = -R ( n(initial)^2 + (n(final)^2 )

I mean technically we can figure out the Rydberg equation using the equation given to us in class. I would use whatever method is best for the parameters we are given in the question.

Re: Rydberg Equation  [ENDORSED]

Posted: Mon Apr 23, 2018 3:10 pm
by Chem_Mod
Prof. Lavelle stresses not using the Rydberg equation because as stated above, you can derive it from the equation given to you in class. He would rather you had a conceptual understanding of where the Rydberg equation comes from than have you just plug and chug.

Re: Rydberg Equation

Posted: Mon Apr 23, 2018 7:59 pm
by Emma Leshan 1B
If we find it faster and easier to use the Rydberg equation on a test or quiz, are we allowed to use it as long as we understand the concepts?