Chemistry revision - The periodic table and elements

There are two types of elements of the periodic table: metals and non metals. All the metal elements are on the left side of the table, leaving the non metals on the right side. There are 8 groups (1,2,3,4,5,6,7,0) and 7 periods.

Dmitri Mendeleev produced one of the first period tables in the 1800’s.

Hydrogen is a different element. It can be listed in group 1 as it has similar properties to the other elements, despite it being a non metal element. This is why it is found in the middle the periodic table.

Molecules and Compounds

Molecules form when two or more atoms chemically bond together.

Compounds can be represented as formulae which tell us the number of atoms of each element there is in a compound.

The reactivity series

This series acts as a ‘league table’, showing which metals are the most to least reactive. The most reactive metal on the series is potassium, and the least, platinum.