2. The periodic table is similar to a big grid that represents elements. It is a chart that shows people all the elements that have been discovered.

3. The order of the periodic table depends on their atomic numbers or weights. Similar to math, it goes from least to greatest, left to right.

4. Back in 1869, a man named Dmitri Mendeleev published the first version of the periodic table. He used many equations and algebraic expressions to place its order and include all the elements discovered in that time.

5. Other names for the periodic table was chemical table or periodic system. Though, over time, it became commonly known as the periodic system.

6. The periodic table is the most important chemistry reference there is. It’s used by many scientists and for many purposes.

7. There are 118 elements in the periodic table today. Ever since Mendeleev published the first periodic table, people have started discovering more elements, and adding them to the table.

8. The rows of the periodic table is called groups, or periods. They line up in a specific order and are well organized.

9. As mentioned earlier, the periodic table is separated into groups. Some of these groups are metals, semi- conductors, non- metals, inert gases, lanthanides, and actinides.

10. The periodic table has extended over time as new elements were discovered and added to the table. Presently, there may be even more elements to be found.