1 Electron Configuration

Question 1

What is the Auf Bau principle?

Answer 1

The principle that electrons fill from the lowest energy to the highest energy level.

Question 2

How many electrons can fill energy levels 1-4 and what orbitals do each energy levels contain?

Answer 2

Energy Level 1= 2e-, Sub-shell: s
Energy Level 2= 8e-, Sub-shells: s & p
Energy Level 3= 18e-, Sub-shells: s,p & d
Energy Level 4= 32e-, Sub-shells: s,p,d & t

Question 3

What is an orbital and how many electrons can it hold?

Answer 3

Orbitals are regions where electrons are likely to be, each orbital can hold up to 2 electrons.

Question 4

What is Hund’s rule?

Answer 4

Orbitals fill up singularly before doubling up.

Question 5

What is the Pauli exclusion principle?

Answer 5

Within an orbital, electrons must have opposite spin.

Question 6

What are the rules for orbitals 4s and 3d? ((2))

Answer 6

Orbital 4s always fills before 3d.
When forming ions, 4s electrons are lost before 3d.

Question 7

How is chromium different to the general rule? (applies to all elements beneath in the same period)

Answer 7

Chromium does not pair in 4s and 3d orbitals.

Question 8

How is copper different to the general rule? (applies to all elements beneath in the same period)

Answer 8

Copper pairs in 3d and not 4s.

Question 9

How many electrons does each orbital hold?

Answer 9

2

Question 10

How many orbitals are in each sub shell?

Answer 10

s= 1
p= 3
d= 5
f= 7

Question 11

What is the order of the way electrons are organised?

Answer 11

Energy Level
Sub - shells
Orbitals