9. Quantum Mechanics
The Energy of Light
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Here it says to calculate the energy for mobile photons with the frequency of 4.29 times 10 to the 15 seconds inverse. Alright. So what we're gonna have here is we have energy and they're giving us frequency. So we're gonna say here, energy of a photon equals Planck's constant times frequency. So that's gonna be 6.626 times 10 to the negative 34 joules times seconds, that's Planck's constant, times our frequency in seconds inverse. So here seconds will cancel out with inverse seconds, and what we get initially is 2.842554 times 10 to the negative 18 joules per photon. Remember, we don't want to round until the very end. So now that we have joules per photon, realize we need to find it in terms of moles of photons. So we're gonna use our conversion factor. So we're gonna say here that we have for every 1 mole of photons, we have 6.022 times 10 to the 23 photons. So here, photons cancel out and I'll have my answer in joules per mole of photons. So this comes out to 1 point 71 times 10 to the 6 joules per mole of photons. So now our answer here has 3 sig figs because our initial value also had 3 sig figs.
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