Question

When sodium compounds are heated in a bunsen burner flame, they emit light at a wavelength of 5890 Angstroms, If 1.0x10^-4 mole of sodium atoms each emit a photon of this wavelength, how many kilojoules of energy are emitted? Please show me how to work this!

Answer 1

Keep in mind that 1 A = \(\sf 10^{-10}~m\)
You can use: \(\sf \color{red}{E= hv}\) where v = frequency = \(\sf \frac{c}{\lambda}\) and \(\sf \lambda\) is wavelength. and \(h\) = planks constant = \(\sf 6.6254 \times 10^{-34}\)