## WK 2 Sapling #5

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

Earl Garrovillo 2L
Posts: 91
Joined: Wed Sep 30, 2020 9:55 pm

### WK 2 Sapling #5

Could someone explain how to find the number of spectral lines when an electron drops from a specific energy level? I'm not sure how to approach this problem.

"The electron in a hydrogen atom is excited to energy level n=6 and emits electromagnetic radiation when returning to lower energy levels. Determine the number of spectral lines that could appear when this electron returns to lower energy levels, as well as the wavelength range in nanometers."

tamara masri_3D
Posts: 52
Joined: Wed Sep 30, 2020 9:35 pm
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### Re: WK 2 Sapling #5

Hey! When an electron drops from 1 energy level to the next, it gives off energy as light. So you can potentially have a spectral line for every time it drops, which would be 5 times.

You can find the wavelengths by plugging the energy levels into the Rydberg equation (v= R{1/n1^2 - 1/n2^2}, where n2 is 6.

Hope this helps!

HannahRobinson3L
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Joined: Wed Sep 30, 2020 9:51 pm
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### Re: WK 2 Sapling #5

The electron that is excited to the n=6 level can emit a photon by moving down to the n=5,4,3,2, or 1 energy levels. And each of these transitions will produce a unique spectral line. For the second part of this problem, the range of wavelengths produced will be from the highest energy transition to the lowest energy transition. Hope this helps!

Anna_Mohling_1D
Posts: 70
Joined: Wed Sep 30, 2020 9:56 pm

### Re: WK 2 Sapling #5

Adding on to what Tamara and Hannah explained, make sure to convert your calculated wavelength from m to nm by diving by 10^-9. I forgot to do this originally and kept getting the incorrect answer.

Katie Phan 1K
Posts: 93
Joined: Wed Sep 30, 2020 9:55 pm

### Re: WK 2 Sapling #5

From n=6, an electron could drop to n= 5,4,3,2,1 so you have 5 spectral lines.
The highest energy transition would be from n=6 to n=1, which would be the lower wavelength when thinking about the range.
The lowest energy transition would be from n=6 to n=5, which would be the larger wavelength when thinking about the range.