Calculate the momentum of a photon of green light, wavelength 515 nm. Chemistry Chapter 9 Calculate the momentum of a photon of green light, wavelength 515 nm. Solution: 1.29 x 10^-27 kg·m/s.w If this photon is traveling in a vacuum, what is its "mass"? Solution: 4.29 x 10^-36 kg Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+