## Finding Wavelength of Light

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

904914037
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Joined: Wed Sep 18, 2019 12:16 am

### Finding Wavelength of Light

Could anyone please explain how to find the wavelength of a light associated with a change in an electron's every level? I will paste an example below, thank you!

"In the hydrogen atomic spectrum, what is the wavelength of light associated with the n = 2 to n = 1 electron transition?"

005391550
Posts: 103
Joined: Thu Jul 25, 2019 12:15 am

### Re: Finding Wavelength of Light

You can use the formula

frequency = -R((1/(n1^2)) - (1/(n2^2))

where R is rydberg's constant, n1 would be 2 and n2 would be 1 for that electron transition

and then you can use that frequency to find the wavelength

Ryan Chang 1C
Posts: 105
Joined: Sat Aug 24, 2019 12:17 am

### Re: Finding Wavelength of Light

Adding on the the post above, wavelength is equal to the speed of light divided by frequency.

Kassidy Ford 1I
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Joined: Sat Aug 17, 2019 12:16 am
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### Re: Finding Wavelength of Light

In lecture Prof Lavelle urges not to use the Rydberg equation if it confuses you but instead to use the H-atom spectrum equation, which is E(n)= -hR/n^2. you do that for both energy states, n=2 and n=1, and then subtract the initial energy from the final energy to get the change in energy. you can then use this energy in the equation wavelength= hc/e to solve for wavelength