Question

Consider a red flame color produced by excited lithium with a wavelength of 671 nm. What is the mass equivalent of 1 mol of photons of this wavelength?

I can get as far as Js of E

Can't seem to find equation to turn Js into mols, or photons into mols, for Js into photons.

I'm lost

Answer 1

E=h*c/lambda Solve for E, the energy in one photon, then multily it by avagradros number.

Answer 2

ahh, of course, thank you.