To the three requirements of a modern Periodic Table, as stated by A. A. Clifford 1, must be added a fourth, namely, that it should be in as close accord as possible with chemical facts, and above all ...

A MODERN table of chemical elements must show electronic configurations as well as the variation in the properties of the elements with atomic number. It should also include the lanthanide and ...

More than a thousand different versions of the periodic table have been created since Dmitri Mendeleev drew the first 150 years ago – but why is one version more familiar to us than practically every ...

The first version of Mendeleev’s periodic table, published in 1869, was reportedly completed in just one day. Historians have pieced together what happened during that day. On the morning of February ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

McGill University provides funding as a member of The Conversation CA. McGill University provides funding as a member of The Conversation CA-FR. The United Nations announced 2019 as the International ...