3.1.1.3 Electron Configuration

Question 1

What are all of the sub-shells?

Answer 1

S, P, D, F

Question 2

How many orbitals and number of electrons are there in each sub-shell?

Answer 2

S - 1 - 2e-
P - 3 - 6e-
D - 5 - 10e-
F - 7 - 14e-

Question 3

What are the two main methods of showing electron configuration?

Answer 3

Arrows in boxes
Sub-Shell Notation

Question 4

How to show the sub-shell notation of Ne

Answer 4

Neon = 1s2 2s2 2p6
The first number is the energy level (shell)
The letter is the sub-shell
The final number is the amount of electrons in that sub-shell

Question 5

What are the 3 main rules when coming to electron configuration?

Answer 5

1. Nobel gas shortening - Use the closest Nobel Gas and add the remaining electrons (E.g Se - [Ar] = 4s2 3d10 4p4)
2. Chromium and Copper - A half subshell is much more stable so one electron from 4s shell jumps to the 3d shell (Cr - [Ar] = 4s1 3d5 and Cu - [Ar] = 4s1 3d10
3. Ionising the transition metals - You remove the electrons in the higher sub-shell first

Question 6

How do you show electrons in boxes and arrows?

Answer 6

Each box represent an orbital.
The arrows are the electrons and the direction they are spinning in.

Question 7

Rules for Arrows in boxes?

Answer 7

1. Electrons fill the lowest energy sub-shell in first
2. Electrons fill orbitals in a sub-shell singly before they start sharing orbitals