The document discusses the periodic table, including how it is arranged by periods and groups. Periods correspond to the number of electron shells, while groups indicate the number of valence electrons. Metals are generally found in the left side and are reactive, forming positive ions by losing electrons. Nonmetals are on the right side and form negative ions by gaining electrons. Noble gases have a full outer shell and are very stable, while halogens form diatomic molecules and colored salts. The reactivity of metals increases down a group as the hold on electrons gets weaker.

1. Periodic Table
Based on the electron configuration
And the reactivity of the elements

3. How the periodic table is arranged

4. Periods
• The horizontal rows are called periods
• The period number corresponds to the number of shells
occupied by the electrons in the atom.
• period 1 - I shell
• Period 2- 2 shells
• Period 3 - 3 shells

5. Groups
• Groups are the vertical columns and are numbered
1-18
• From the group number you can work out the
number of electrons in the outer shell
• The last digit of the group is the number of electrons
• Group 12 has 2 electrons in the outer shell
• Group 18 has 8 electrons

6. Metals and non metals

7. Types of metals

8. Properties of metals and non metals
• Practical activity 4:1
• To compare the properties of metals and non
metals.
• Draw table and investigate.

9. Groups 1 and 2 alkali metals and
alkaline earth metals
• Group 1 and 2
• Far too reactive to be found naturally in
their pure form.
• Display similar extreme chemical behavior.
React violently with water producing an
alkaline solution and H2
• Form +1 ions (How? Hint: How many
electrons in the outer shell and how
many protons left?)
• Group 2 form 2+ ions.
• All react with group 17 (halogens)
especially chlorine gas to produce salts.

10. Transition metals
Groups 3-12
• Are all metals and include
most useful colorful and
valuable metals.
• Solutions and salts are also
colorful
• Relatively hard with high
melting points
• Iron copper zinc gold and
silver
• *Special group does not
follow the outer e shell rule

11. Trends in chemical activity of metals
• Metals atoms have a weak hold on the outer shell electrons
(valence electrons)
• As you move down a group more shells so the hold gets
weaker and weaker.
• This makes the the metal more unstable and hence more
reactive.
• Metals in group 1 are usually stored in paraffin oil to keep
them moisture free

12. Noble gases group 18
• Colourless and occur naturally in the
atmosphere.
• Incredibly stable: have 8 electrons in
the outer shell
(very desirable. eg Disneyland)
• Helium lightest eg party balloons and
stable unlike hydrogen Hindenburg
• Gases get heavier as go down the
group.
• Sometimes called inert gases.

13. The halogens group17
• Are not found in nature in their pure
form but are found in various types
of salts.
• All form molecules made up of 2
atoms eg F2 , Cl2 , Br2 etc
• Have coloured and poisonous vapour
• Form ions with a -1 charge
• Get bigger and less reactive as you
move down the group.
• Halogen light are much brighter than
normal globes

14. • Comparing the group number to the valence electrons.
• Determining the ion formed for the elements and why