Calculating wavelength of light

[viper2308]

Homework Statement

It takes 208.4 kJ of energy to remove 1 mole of electrons from an atom on the surface of rubidium metal.
What is the maximum wavelength of light capable of doing this?

Homework Equations

Ephotons=hc/lambda

The Attempt at a Solution

I don't know the energy of the photon. I know h=6.626e-34, c=2.9979e8
I'm trying to find lambda but w/o the Ephoton I don't how to solve the equation.I found the energy to remove a single electron which is 3.461e-19.

 

[mgb_phys]

If you assume that the 208.4kJ was from identical wavelength photons of just the minimum energy to remove the electron, you could work out the energy per photon then use E = hc/lambda to work out the wavelength.

 

[viper2308]

Thank You, I was using the wrong energy.