Periodic table film
Demonstrated reaction of sodium and potassium with water.
Here is potassium – a soft metal, stored in oil
Cut to expose a shiny surface
Reacts violently with water
And leaves behind an alkaline solution
Sodium is very similar though a bit less reactive.
They are alkali metals
Reaction of magnesium with oxygen (air)
Then dissolve the oxide formed in water
This slowly produces and alkaline solution
Magnesium is an alkali earth metal
The periodic table
Elements are arranged in the periodic table in order of increasing atomic number.
Elements can be categorised as metals and non-metals.
The stepped line to the right of the periodic table separates the metals and non-metals.
In the periodic table each row is called a period and each column is called a group.
Elements in the same group tend to have similar chemical properties. Some are given names –
group 1 – alkali metals
group 2 – alkaline earth metals
group 7 – halogens
group 8 or 0 – noble gases
The transition metals are in a block in the centre of the periodic table.