Answer
If you want to understand substances, you have to understand the basic components (atoms and molecules) that make them up; Ex - carbon dioxide is made up of carbon and oxygen atoms
Work Step by Step
The main goal in chemistry is to understand the substances around us, and we do so by studying the atoms and molecules that make it up.
Carbon dioxide is made up of 1 carbon atom and 2 oxygen atoms. Another example is carbon monoxide which is made up of 1 carbon atom and 1 oxygen atom.