The allegory not only draws on the theory of forms, but it is connected both to the concept of forms and Plato's theory of the stages of life. 1  At the lowest stage, the cognitive stage of imagination (in Greek, eikasia), the prisoners exist bound and hindered in their perspective.
Since any orbital can hold a maximum of two electrons, the bonding orbital in H 2 + is only half-full. This single electron is nevertheless enough to lower the potential energy of one mole of hydrogen nuclei pairs by 270 kJ quite enough to make them stick together and behave like a distinct molecular species.
In a neutral atom, the number of electrons is the same as the number of protons. The atomic number of aluminum is 13. A neutral atom of aluminum has 13 protons and 13 electrons. The ground state electron configuration for aluminum is #1s^22s^22p^63s^23p^1#. A shorthand way to write the electron configuration, called noble gas notation, is #[Ne]3^23p^1#.