1.6 To understand the difference between elements, compounds and mixtures.

Elements are made of only one element, e.g. O2  is two oxygen atoms bonded together.  Different elements are defined by their number of Protons.
Compounds are different elements chemically bonded, i.e. more that one element chemically joined e.g. H2O is two hydrogen atoms and one oxygen atom chemically joined.
Mixtures are different chemical compounds or atoms mixed together but not chemically joined to one another