1.1 Atomic Structure - Electronic Structure

Question 1

Principal energy levels:

Answer 1

Electrons can be arranged in shells of different energy which are called principal energy levels/ quantum shells.
Lower energy levels are nearer the nucleus and higher energy are further away from nucleus.

Question 2

Sub-levels:

Answer 2

Principal energy shells are divided into sub-levels with slightly different energies

Question 3

Orbitals:

Answer 3

Sub-levels are made up of orbitals which can are 3D volumes in which there is a high probability of finding an electron and each orbital can hold a max. of 2 electrons.
Different types of of orbitals have different shapes.
The two electrons in each orbital spin in opposite directions

Question 4

S sub-shells:

Answer 4

Consist of 1orbital holding 2 electrons
In all 4 quantum shells
Spherical shape

Question 5

P sub-shells:

Answer 5

Consists of 3 orbitals holding 6 electrons
In quantum shells 2-4
‘8’ shape

Question 6

D sub-shells:

Answer 6

Consists of 5 orbitals holding 10 electrons
In quantum shells 3-4

Question 7

F sub-shells:

Answer 7

Consists of 7 orbitals of 14 electrons
In quantum shell 4

Question 8

Electronic configurations of elements:

Answer 8

Fill the lowest energy sub-shells first (the 4s sub shell has a lower energy than 3d even tho its quantum number is greater so it fills first)
Electrons fill orbitals singly before the start pairing
For the configuration of ions from the s and p blocks of the periodic table just add of remove electrons from the highest occupied sub-level
Noble gases are also sometimes used in electronic configurations e.g. Ca can be written as [Ar]4s2

Question 9

Transition metals:

Answer 9

Chromium and copper act unusually as they donate one of their 4s electrons to the 3d sub-shell to become more stable with a half full 4s sub-shell
When transition metals become ions, they lose their 4s electrons before their 3d electrons

Question 10

Chemical properties of group 1 and 2:

Answer 10

S-block elements which have 1 or 2 outer shell electrons
These electrons are easily lost to form positive ions with an inert gas configuration

Question 11

Chemical properties of group 5, 6 and 7:

Answer 11

P-block elements can gain 1, 2 or 3 electrons to form negative ions with an inert gas configuration
4-7 also share electrons when covalently bonding

Question 12

Chemical properties of group 0:

Answer 12

Have full p and s shells so do not gain/lose electrons - they are inert

Question 13

Transition metals:

Answer 13

D block elements which tend to lose s and d electrons to form positive ions