The properties of a photon [ENDORSED]

[nathansalce 3e]

Can somebody better explain how a photon is both a particle and a wave? I understand that it acts like both, but in what situations does it act like wave and vice versa?

[Chem_Mod]

There are many different experiments that show the wave or particle properties of light. Mainly, the fact that light produces diffraction and interference patterns show it's wave-like properties, while the photoelectric effect supports light as a particle.

[Chem_Mod]

When we are referring to its ability to emit an electron, we think of photons as packets of energy, or particles. If one “particle” doesn’t have enough energy to emit an electron, it doesn’t matter how many we throw at a peice of metal. No matter what, an electron will not be emitted. Professor Lavelle used the example of trying to jump over a barrier. If you and your friends dont have enough energy to jump over 3 feet, it doesn’t matter how many of you try. You’ll never make it over.

However, when we refer to a wave, we can see that by shining a light through two slits in a paper, we get a diffraction pattern where the waves overlap. If they were particles, it should only produce a straight beam of light through the holes.

These are key concepts of Quantum Chemistry, so if you are still struggling with them, I highly encourage you to go to Peer Learning Sessions or Office Hours to get help!