Chemistry Help, please! Photon Energy?
I need help figuring out how to do this problem, please!
The energy required to dislodge electrons from sodium metal via the photoelectric effect is 275 kJ/mol. What wavelength in nm of light has sufficient energy per photon to dislodge an electron from the surface of sodium?
The answer is 435 nm, but I'm not sure how to get to that answer :(. I know that E = hc/wavelength, but how can I get rid of the "mol" in kJ/mol?
Any help would be greatly appreciated!!
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Just divide by the number of electrons per mole (or multiply by moles per electron). Avogadro's number.
275 kJ/mol * 1/6.022x10^23 mol/electron => 4.57 x 10^-19 J/electron
wavelength = hc/E
wavelength = 1.986 x 10^-25 J m / 4.57x10^-19 J
wavelength = 4.35 x 10^-7 m
urm. nicely capability of a photon is comparable to plancks consistent cases the cost of light divided by skill of the wavelength. checking your gadgets this might desire to provide you joules. i assume you will possibly then multiply this selection by skill of a mole.