Chemistry 60 Help

Question

How many photons are produced in a laser pulse of 0.796 J at 449 nm?

Answer 1

E = hc/λ

E = (6.626x10^-34 J-sec)(3x10⁸ m/sec) / 449x10^-9 m

E = 4.43x10^-19 J / photon

0.796 J x 1 photon/4.43x10^-19 J = 1.80x10¹⁸ photons