(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

When ultraviolet radiation of wavelength 58.4 nm from a helium lamp is directed on to a sample of krypton, electrons are ejected with a speed of 1.59 Mm/s. Calculate the ionization energy of Krypton.

2. Relevant equations

E=hv, [itex]\frac{1}{λ}[/itex]=R(1- [itex]\frac{1}{n^{2}}[/itex] ) <- Lyman series

Ionization energy = [itex]\frac{hcR}{n^{2}}[/itex]

3. The attempt at a solution

I used the Lyman series to try and find the Rydberg constant for Krypton (with n=4), then substituted that value into the Ionization energy equation with n = 4 again. I'm given that the answer should be 14 eV, but I didn't get that result.

My confusion is how these equations relate to the ionization of krypton since the equations assume a single electron atom, which krypton is not. Furthermore, I can't find a use for the velocity (E= 0.5mv^{2}also doesn't give the correct answer).

Any help in figuring out how to approach this problem would be greatly appreciated.

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# Homework Help: Ionization Energy (Quantum Mechanics)

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