## Calculate energy required to remove an electron

Chem_Mod
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### Calculate energy required to remove an electron

I am having trouble calculating the energy required to remove an electron from a sodium atom. The given information includes the ejected electron's velocity (6.61 x 10^5 m/s) and sodium's work function (150.6 kJ/mol). How would I solve this problem?

Chem_Mod
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### Re: Calculate energy required to remove an electron

1) Calculate the electron's kinetic energy using E(k) = 1/2 mv^2. This is the 'excess' energy. 2) electron's kinetic energy + sodium's work function (per atom) = energy of incoming photon. 3) However your question above asks for "the energy required to remove an electron from a sodium atom" which is simply the work function (per atom).

Cali Rauk1D
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### Re: Calculate energy required to remove an electron

All you would have to do is use 150.6kJ/mol and divide by 100 and get 1.506 and raise to 10^5.

StephanieRusnak
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### Re: Calculate energy required to remove an electron

Use the equation: kinetic energy of ejected photon = energy supplied by photon - work function (energy required to eject electron)

gabbym
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Joined: Wed Apr 11, 2018 3:00 am

### Re: Calculate energy required to remove an electron

This was so helpful, thank you!

StudentD2B
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Joined: Fri Sep 28, 2018 12:27 am

### Re: Calculate energy required to remove an electron

Why do you multiply by 10^5?

Ronald Thompson 1F
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Joined: Fri Sep 28, 2018 12:25 am

### Re: Calculate energy required to remove an electron

10^5? I thought you would just convert from KJ to J?