Quantized Energy Level

[Michelle Dong 1F]

What exactly does it mean when it says energy levels are quantized? I'm confused on the concept of the word "quantum."

[Vivian Nguyen]

"Quantum" means "the smallest possible discrete unit of any physical property", so how I understand it is how measurements are restricted to certain packets/quantities. For example, Dr.Lavelle used water buckets to illustrate the point. Each bucket represents the smallest discrete unit of water in this example, so as you pour more buckets of water into a tub, you will be measuring in quantized units of buckets...like "five buckets of water".

For energy levels, each level has a specific quantity of energy, a specific packet - that's why it is quantized. The transition from each energy level to another has a set threshold that must be fully reached to go from one level to another.

Hope this sorta makes sense...! I'm sure someone else in the community can explain it better haha

[Salman Azfar 1K]

For the purposes of this topic, it generally means that the energy levels are going to be whole numbers n=1, n=2 etc. You cannot send in a photon with enough energy to move an electron to say, n=2.5 or else the photon will pass through rather than being absorbed by a sample.

[Justin Chang 2K]

Yeah, especially when you discuss energy levels of the atom, if the photon does not have the exact amount of energy to go from n=1 to n=2, the electron won't be excited, even if the energy allows the electron to go from n=1 to n=2.5. It must be whole numbers in this case, hence why numbers are quantized.

[Reyna Alonso 1E]

I just wanted to add that Quantum also means "how much?'

[Chem_Mod]

When energy is quantized, it means the energy can no more be arbitrary continuous value, but restricted to certain discrete value.