Major purpose of this lecture is to present on chemical Element. A element is a pure substance made of one type of atom, they are divided into metals and non-metals. Examples of non-metal elements include carbon, oxygen, hydrogen, and nitrogen. Examples of metal elements include aluminum, iron, copper, and gold. This lecture also focus on ‘atoms.’ They are not the smallest things we know of, but they are so small we can’t see them except with the most powerful microscopes.