## Chemistry 10th Edition

$3.022\times10^{-19}J/photon$
The energy per photon is given by: E = hν = $\frac{hc}{λ}$ We know: h = $6.626\times10^{-34}Js$ c = $2.997925\times10^{8}ms^{-1}$ λ = 6573 Å = $6573\times10^{-10}m$ Thus: E = $\frac{6.626\times10^{-34}Js\times2.997925\times10^{8}ms^{-1}}{6573\times10^{-10}m} = 3.022\times10^{-19}J$