I'm having a bit of trouble understanding basic atomic structure. Do the electrons of 2 different elements have different energy levels? For example beryllium and boron. Are the 1S electrons of Be in its ground state occupying the exact same energy level of the 1S electrons of B in its ground state? Also I assume s and p orbital electrons are at different energy levels but what about the different p orbitals? Do they have 3 different energy levels or are all 6 atoms in the p orbital in the same energy level?
The 1s state of any element is the lowest energy level. However, the energy of that level (and the rest) varies according to the specific element. So, the 1s electrons of Be are not at the same energy as 1s electrons in B. The electrons in an s, p, d or f shell ordinarily have the same energy. However, those levels can be split into sublevels through the application of an external magnetic field, and by various other means. When several electrons share the same energy, the level is said to be degenerate, so a p orbital, for example, normally has a degeneracy of 6. Every electron in an atom has a unique set of four quantum numbers, designated \(n,l,m_l\) and \(m_s\). The energy of the level in the absence of external fields etc. is normally determined by the numbers n and l. The value of n is the principal quantum number, and is the number that appears in a shell label like 3f (n=3). The value of l has to do with the orbital angular momentum of the electron. Its value determines the letter designation of a shell, according to the following scheme: l=0: s l=1: p l=2: d l=3: f l=4: g l=5: .... So a 3f orbital has n=3, l=3, for example. The 6 electrons in a p orbital, each have different combinations of the other two quantum numbers, which relate to the orientation of the orbital angular momentum and to the electron spin direction, respectively. Different values of those numbers do not ordinarily change the energy of the state, however.
