THE PERIODIC TABLE
O Level Chemistry – Chapter Notes
Periodic table : The Periodic Table is a systematic arrangement of all known
elements, organized by increasing atomic number and grouped by similar
properties.
Periodic table is divides into:
Periodic groups
Propertices of element across period:
Group: 1 2 3 4 5 6 7 8
Symbol: Na Mg Al Si Ph S Cl Ar
Name: Sodium Magnisium Aliminum Silicon Phosphorus Sulfur Chorine Argon
Propertices: Metallic Metalloid Non-
metallic
Nature of Basic Amputeric Acidic
oxides:
, 1. Going down a group, the elements becomes more metallic.
2. Elements in the same period have the same number of electron
shells.
3. Elements in the same group have: * The same number of valance electrons ;* Similar
chemical properties.
4. Elements in Group 1 to 3 form positive ions, e.g. Na , Mg and Al.
5. Elements in Group 4 to7 form negative ions, e.g. O and F.
Group- Alkali ( I )
The elements in group-1 of the Periodic table is divides into: table
are called Alkali metal.
Li Physical properties:
They are soft and can be cut.
Na Have low melting and boiling point.
Have love densities. Lithium, sodium and potassium float on
water.
K Chemical properties:
Alkali metals react with cold water to form alkali and
Rb hydrogen gas.
Alkali metals are powerful reacting reducing agents.
Alkali metals are powerful reducing agents.
Alkali metals form ionic components.
Cs Their reactivity increases down the group.
Fr How do the physical properties change going down group1?
Melting and boiling point of alkali metals decreases.
The densities of alkali metals generally increases.
O Level Chemistry – Chapter Notes
Periodic table : The Periodic Table is a systematic arrangement of all known
elements, organized by increasing atomic number and grouped by similar
properties.
Periodic table is divides into:
Periodic groups
Propertices of element across period:
Group: 1 2 3 4 5 6 7 8
Symbol: Na Mg Al Si Ph S Cl Ar
Name: Sodium Magnisium Aliminum Silicon Phosphorus Sulfur Chorine Argon
Propertices: Metallic Metalloid Non-
metallic
Nature of Basic Amputeric Acidic
oxides:
, 1. Going down a group, the elements becomes more metallic.
2. Elements in the same period have the same number of electron
shells.
3. Elements in the same group have: * The same number of valance electrons ;* Similar
chemical properties.
4. Elements in Group 1 to 3 form positive ions, e.g. Na , Mg and Al.
5. Elements in Group 4 to7 form negative ions, e.g. O and F.
Group- Alkali ( I )
The elements in group-1 of the Periodic table is divides into: table
are called Alkali metal.
Li Physical properties:
They are soft and can be cut.
Na Have low melting and boiling point.
Have love densities. Lithium, sodium and potassium float on
water.
K Chemical properties:
Alkali metals react with cold water to form alkali and
Rb hydrogen gas.
Alkali metals are powerful reacting reducing agents.
Alkali metals are powerful reducing agents.
Alkali metals form ionic components.
Cs Their reactivity increases down the group.
Fr How do the physical properties change going down group1?
Melting and boiling point of alkali metals decreases.
The densities of alkali metals generally increases.
