The Periodic Table of the Elements, more commonly called the Periodic Table, is an arrangement of all the elements known in the entire universe. Some elements are hypothetical; that is, they haven't been discovered but scientists expect to find them at some point!
What is an element?
An element is a substance (material) that can't be broken apart into simpler substances; that is, it's a pure substance.
What are the numbers on each element on the Table?
These are called Atomic Numbers. Every element has an atomic number. The atomic number tells how many protons (positively charged particles in the center of the atom) are in one atom of the element. The atomic number increases in order from left to right across the table in each row, as shown below:
Each row of elements is called a period; hence the name Periodic Table. Each column of elements is known as a group or a family.
The atomic number also tells how many electrons (Negatively charged particles surrounding the atom's center) are in the atom.
Interactive Periodic Table
This is an interactive Periodic Table of the Elements! Click any of the buttons below to learn more about the element...
Hydrogen and the Alkali Metals
Alkaline Earth Metals