This document contains a chemistry teacher's lesson plans about the periodic table and trends in the properties of elements in Period 3. The lessons cover identifying the s-, p-, and d-blocks in the periodic table, trends in melting points, boiling points, atomic radii, ionization energies, and electronegativity across Period 3. Students are asked to label diagrams, produce charts displaying atomic number and melting point trends, define key terms, and explain observed trends in terms of atomic structure and bonding.

1. Mrs Carberry
AMDG
Specification reference 3.1.4
Periodicity
Lesson 1
The Periodic Table
Learning Objectives
Where are the s-, p- and d-blocks of elements in the
periodic table?

2. Mrs Carberry
Use the diagram on page 72 to name the areas of the periodic table.
Draw a line to show where the metals and non-metals are.
Number the groups and periods.

3. Mrs Carberry
Use the diagram on page 73 to label the s-, p-, d- and f- blocks.
Why are they labelled in this way?

4. Mrs Carberry
Colour in period 3.
Check your knowledge!
Answer the summary questions on page 74 then
mark them.

5. Mrs Carberry
Group 1 2 3 4 5 6 7 0
Element
Electron
Arrangemen
t
Block
Structure
Melting
Point (K)
Boiling
Point (K)
Atomic
radius
Nuclear
charge
First
Ionisation
energy
Use
Chapter
4
to
fill
in
the
table
with
information
about
Period
3

6. Mrs Carberry
AMDG
Specification reference 3.1.4
Periodicity
Lesson 2
Trends in the properties of elements
of Period 3
Learning Objectives
What are the trends in melting and boiling
temperatures of the elements in Period 3?
How can these trends be explained in terms of
bonding and structure?

7. Mrs Carberry
Melting Points – ICT Task
Melting Points
Element Symbol Atomic
Melting
Point
Number K
argon Ar 18 84
chlorine Cl 17 172
phosphor
us P 15 317
sodium Na 11 371
sulphur S 16 392
magnesiu
m Mg 12 922
Produce a suitable
chart to display atomic
numbers and melting
points.
Do you notice any
trends, this is difficult
with a limited data set,
in the metal and non
metal groups?
Can you explain your
observation in terms of
the structure of the
element, E.g. metallic,
covalent, ionic,
molecular …?

8. Mrs Carberry
AMDG
Specification reference 3.1.4
Periodicity
Lesson 3
More trends in the properties of elements of
Period 3
Learning Objectives
What are the trends in atomic radius and first
ionisation energy of the elements in Period 3?
How can these trends be explained?

9. Mrs Carberry
Write a definition….
Atomic radius -
First ionisation energy -
Periodicty -

10. Mrs Carberry
Write a definition….
Atomic radius – Atomic radii are taken to be half the distance
between the centres of a pair of atoms.
First ionisation energy – The energy required to remove a mole of
electrons from a mole of gaseous atoms, to form one mole of
gaseous unipositive atoms.
Periodicty (Periodic trend) – The regular recurrence of the
properties of elements when they are arranged in atomic number
order as in the Periodic Table.

11. Mrs Carberry

12. Mrs Carberry
Explain why a sulphur atom has a smaller atomic radius than
phosphorus (3)
Explain why the first ionisation energy increases across the third
Period.(3)
Explain why electronegativity increases across the period. (3)
Describe and explain the trend in electronegativity values down
Group 2 (3)
[Total 12]

13. Mrs Carberry
Explain why a sulphur atom has a smaller atomic radius than
phosphorus
Both cases the outer electrons are in the third quantum shell
The greater nuclear charge of sulphur
Draws the electrons closer
Explain why the first ionisation energy increases across the third Period.
Electron is removed from the same principal energy level
Nuclear charge steadily increases across the period
Making it increasingly difficult to remove an electron.
Explain why electronegativity increases across the period.
Across the period atomic radius decreases
Nuclear charge increases
Resulting in a greater attraction for the electrons in a covalent bond.
Describe and explain the trend in electronegativity values down Group 2
Electronegativity decreases
Down the group, since more principal energy levels are occupied
But nuclear charge increases

14. Mrs Carberry
AMDG
Specification reference 3.1.4
Periodicity
Lesson 4
A closer look at ionisation energies
Learning Objectives
Why is the increase in ionisation energies across
a period not regular?
How do successive ionisation energies explain
electron arrangements?

15. Mrs Carberry
First ionisation energies (enthalpies) for
Period 3
1. Explain the
drop between
groups 2 and
3
2. Explain the
drop between
groups 5 and
6
HINT
Use electron
arrangements to
help you explain

16. Mrs Carberry
Successive ionisation energies
Can you explain
how successive
ionisation energies
are evidence for
electron shells?
SODI
UM