Question

What is the binding energy in eV of electrons in magnesium, if the longest-wavelength photon that can eject electrons is 337 nm?

Answer 1

frequency = velocity of light c / wavelength in meters
c = about 3 * 10^8 m/s
energy = Planck's constant * frequency
Plank's constant is 6.626 * 10^-24 Joule seconds

Answer 2

typo
6.626 * 10^-34 Joule seccondss