How many energy shells have electrons in them in a silicone atom?

Answer 1

An electron/energy shell, is a group of atomic orbitals with the same value of the principal quantum number n.
Thus in a silicon atom (1s^2 2s^2 2p^6 3s^2 3p^2) the number of energy shells with electrons in them is 3.

(just for info: There are 5 occupied subshells (1s, 2s, 2p, 3s, 3p) and 8 occupied orbitals 1s 2s 2px 2py 2pz 3s 3px 3py, out of which the first 6 have 2 electrons and 3px and 3py have one electron each; Hund's rule doesn't allow an electron pair in 3px while the other 3p orbitals are empty)

Answer 2

Well its electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^2.

I would say that 7 energy shells have electrons in them.

Although I might be confused with energy shells. It might be that 7 orbitals have electrons in them and and just 5 energy shells have electrons in them?

Answer 3

You did mean silicon (Z=14) right?

Otherwise I might say two, but Pauli would say one. Silicone energy levels that is. Silicone.

Hund's rule. Now that's funny. unfilled s-shells and all that. How can it be a "rule"? It's just a guide. Silly silly scientists and engineers believing their textbooks like a gift from God.

Suggestion: THINK. :)