2.2.1 Electron Structure

Question 1

How many electrons can fill the first four shells?

Answer 1

Shell 1 = 2
Shell 2 = 8
Shell 3 = 18
Shell 4 = 32

Question 2

What is an atomic orbital?

Answer 2

A region around the nucleus that can hold up to two electrons with opposite spins

Question 3

What is the shape of an s-orbital?

Answer 3

A spherical shape

Question 4

What is the shape of a p-orbital?

Answer 4

A dumbbell shape

Question 5

How many orbitals make the the s-shell and how many electrons can it hold?

Answer 5

• 1 orbital
• 2 electrons

Question 6

How many orbitals make the the p-shell and how many electrons can it hold?

Answer 6

• 3 orbitals
• 6 electrons

Question 7

How many orbitals make the the d-shell and how many electrons can it hold?

Answer 7

• 5 orbitals
• 10 electrons

Question 9

How do you fill the orbitals?

Answer 9

• Orbitals are filled in order of increasing energy
• 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p
• Orbitals are occupied singularly before paring

Question 10

What is subshell notation?

Answer 10

First number = shell
Second letter = sub shell
Third number = number of electrons in sub shell

Question 11

How do you find the electronic configuration of an ion?

Answer 11

4s electrons are lost before 3d electrons

Question 12

What are the irregular electronic configurations of copper and cromium?

Answer 12

• Half filled or fully filled sub levels add stability
• Electron is promoted to half fill or fully fill a sub level

Cu = 1s2 2s2 2p6 3s2 3p6 4s1 3d10
Cr = 1s2 2s2 2p6 3s2 3p6 4s1 3d5