# Choose out the spectrum

1. Mar 11, 2009

### MonsieurWise

Uhm...I'm doing some experiment with some unknown gas tubes. I have a spectrum when I use the grating. Can I, by some ways, use the quantum numbers to identify what the gas inside is...? I've heard of one method, but I could not find the name. Thank you in advance.

2. Mar 12, 2009

### Dr Transport

In principle you can, if you can find out the whether or not it is an atomic species or diatomic species you should be able to figure out the gas.....

3. Mar 12, 2009

### MonsieurWise

Oh yeah, I used only atomic species (like just Lithium gas or hydrogen gas, is that what u mean...?). Is there a way I can identify the mystery gas?
The way I'm trying right now is to use the equation 1/lambda = RZ^2 (1/n_f + 1/n_i), play around with the numbers to guest n_f and n_i, plot the points on a graph, with (1/n_f + 1/n_i) on the x-axis and (1/lambda) for y-axis. The linear best fit line should give me a slope of RZ^2, and that would be how I find Z, thus the element.
However, I found this method is way too simple and I can just apply it to small atoms, such as Hydrogen or Helium. For big atom like Oxygen...well, I failed miserably. I searched but find no other methods to include the others quantum numbers into calculation. Could you show me a website that introduce the method?
this is the first time I've done anything with Quantum Physics...sorry if my questions seems stupid...
Thank you very much!