Instructor: Mark Pearcy. Plato's allegory of the cave is one of the best-known, most insightful attempts to explain the nature of reality. The cave represents the state of most human beings, and the tale of a dramatic exit from the cave is the source of true understanding.
We also have to know how many electrons can fit into each state. There is only one s-orbital per shell, and it can hold a total of 2 electrons. There are three total p-orbitals (ml = -1,0,1) that can hold a total of 6 electrons (because each ml can have an ms of +1/2 or -1/2. There are five d-orbitals (ml = -2,-1,0,1,2) that can hold a total of 10 electrons. Here's an example to help put this in context. We need to write the electron configuration for an oxygen atom. First, go to the periodic table and find how many electrons oxygen has.
Two of them will be found in the 1s orbital close to the nucleus. The next two will go into the 2s orbital. The remaining ones will be in two separate 2p orbitals. This is because the p orbitals all have the same energy and the electrons prefer to be on their own if that's the case.