An element is a pure substance which is composed of only one kind of atom.

The periodic table provides an organization of all of the known elements. I'll expect you to memorize the first twenty element (know their name and symbol) and a number of common elements. I'll also expect you to know the phase of every element in the periodic table.

What does an element look like? If it consists only of atoms we could use a single circle/sphere (), if it consisted of molecules with two atoms it would look like (). One element has eight atoms in the molecule. That element is sulfur and a sulfur molecule would look like;

The formula of the element sulfur is S₈.