150 years ago, Russian chemist Dmitrii Mendeleev created the periodic table of the elements, revolutionizing chemistry. Skip to content. Subscribe or renew today ...

Explore the periodic table, and build atoms and molecules in this web edition of the NOVA Elements iPad App. It's Elemental In this interactive periodic table, explore the elements and their ...

It's Elemental. By Kate Becker; Posted 05.12.11; NOVA; Whether they are created by nature or in the lab, chemical substances are all made of some combination of just 118 pure elements.

Mendeleev also did something special with the gaps on the table. All the early periodic tables had holes where no known element fit. We know today they simply hadn't been discovered yet.

Although some of the symbols on the periodic table may seem strange, they all make sense with a little background information. For example, the symbol for the element mercury, ...