All matter is made of s.
An element is a substance consisting of only one type of .
s are the smallest part of an element that can take part in a chemical change.
Examiner Tip
Distinguish clearly between an atom and an element. An atom is the smallest unit, while an element is a collection of identical atoms.
The concept of atoms dates back to ancient Greek philosophers, but it was only in the 19th century that John Dalton provided the first scientific atomic theory.