Everything is made of atoms. Atoms themselves are made of smaller particles. Elements can join together in different ways to form compounds with different properties.
When elements combine or join together new substances are formed. These substances are called compounds.
This is shown in the diagram below
There are millions of different compounds and all of them have different properties. The properties of compounds are linked to the type of bonds formed within them.
Naming compounds is easy if you follow these 3 simple rules.
The element that is furthest left in the periodic table comes first, eg Sodium Chloride/Carbon dioxide
If there are only two elements in the compound then the compounds name ends in –ide, eg A compound of copper and sulfur is called copper sulfide.
If the compound contains three elements one of which is oxygen then the compound name will end in –ate or –ite, eg Calcium carbonate contains calcium, carbon and oxygen.
Sometimes the name of the compound gives information about the formula of that compound. Names of these compounds have prefixes that give the number of atoms of certain elements in each molecule.
Prefix | Number of atoms |
Mono- | One |
Di- | Two |
Tri- | Three |
Tetra- | Four |
Penta- | Five |
Hexa- | Six |
Example – Carbon monoxide contains one carbon atom joined to one oxygen atom, so it has the formula CO.