Can you name everything from Ac to Zr? Test your knowledge of the periodic table and see if you can top the leaderboard ...

Discover the intelligent design of the periodic table with BBC ... Each square in the table contains an element symbol of one or ... For example, the third period contains sodium (Na) to argon ...

Elements in the periodic table are arranged in order of increasing atomic number. The atomic number represents the number of protons in an atom's nucleus, uniquely identifying each element.

International Year of the Periodic Table: 150th Anniversary of Dimitri Mendeleev's Genius Creation Published Jan 07, 2019 at 11:21 AM EST Updated Jan 07, 2019 at 11:24 AM EST Today’s periodic table.

The periodic table is a powerful symbol of science past, but can also point to the future. Credit: Sean Gallup/Getty. At first glance, the system of chemical elements published by Dmitri Mendeleev ...