## Atomic Spectra Chapter 1 #15 HW problem

H-Atom ($E_{n}=-\frac{hR}{n^{2}}$)

Isabella Shahmirza 2H
Posts: 30
Joined: Fri Sep 25, 2015 3:00 am

### Atomic Spectra Chapter 1 #15 HW problem

In problem #15, we are given that a line is observed at 102.6nm in the UV spectrum of atomic hydrogen. We have to determine the values for "n" for the initial and final energy levels of the electron during the emission of energy. I know that the initial is n=1 because we are in the UV spectrum. In order to find what the final energy level is equal to, do we calculate the frequency (from the given wavelength) and set that equal to $\frac{-hR}{n_{f}^{2}}-(\frac{-hR}{1^{2}})$; or do we calculate the change in energy from the frequency (using $E=h\nu$) and set that equal to the equation to find the final energy level. I tried both ways, and I am not getting the correct answer. Is there another way to determine the final energy level, n?

Katie Clark 3B
Posts: 26
Joined: Fri Sep 25, 2015 3:00 am

### Re: Atomic Spectra Chapter 1 #15 HW problem

I solved for the frequency using the given wavelength. I then pugged that value and n=1 into the equation from the book: $\nu =R(\frac{1}{n_{f}^{2}}-\frac{1}{n_{i}^{2}})$. I plugged in n=1 to the first n in the equation. I then solved for the second n and found it to be equal to 3. Hope this helps!

Aneel Ramirez 1A
Posts: 14
Joined: Fri Sep 25, 2015 3:00 am

### Re: Atomic Spectra Chapter 1 #15 HW problem

I am still struggling with this question. I understand how to calculate the wavelength when given values of n, but I don't quite understand how to find the values of n when given the wavelength? Could someone please explain and further clarify how we use these equation to find the values for n?