What is an Element?
An element is a pure substance made of only one type of atom. It cannot be broken down into a simpler substance by chemical means.
Think of elements as the basic letters of the alphabet. You can't simplify the letter 'A' any further!
Examples: Oxygen (O), Gold (Au), Helium (He), Carbon (C)
O
O
O
All the same type of atom.
What is a Compound?
A compound is a pure substance made of two or more different types of atoms that are chemically bonded together in a fixed ratio.
If elements are letters, then compounds are like words. They are formed by combining letters in a specific way.
Examples: Water (H₂O), Table Salt (NaCl), Carbon Dioxide (CO₂)
H
O
H
H
O
H
Different atoms chemically joined.
Check Your Understanding
Is this substance an element or a compound?