According to Hund's rule of maximum spin multiplicity, how many singly-occupied orbitals are there in the vale

Question

According to Hund's rule of maximum spin multiplicity, how many singly-occupied orbitals are there in the valence shells of the following elements in their ground states? Enter your answer as the sum of all the orbitals (for example 15).
A) beryllium
B) nickel
C) chlorine
D) neon
E) scandium
F) germanium

Answer 1

Just look at each atom's atomic number and fill out an energy diagram....for example, Beryllium is atomic number 4. So...
| = electron

2s -|-- 2p -|-- --- ---
1s -|-|-

Beryllium has 2 singly-occupied orbitals.


Neon, a noble gas, has its valence shell perfectly filled and has no open spaces. That is why the noble gases are so stable.

For atoms with large atomic numbers, look at what column they are in. For more information, search around...there are plenty of helpful websites that can be found. I just searched "Valence electrons" and here's what I came up with:

Answer 2

I tossed out the rulebooks when *they* told me Pluto was no longer a planet.