The periodic table

The United Nations have proclaimed 2019 to be the International Year of the Periodic Table of Chemical Elements (IYPT 2019) to mark the 150th anniversary of the classification system that decorates chemistry classrooms and labs around the world. Since its inception in 1869, the periodic table has evolved significantly as the number of known elements has increased, along with our understanding of them. We celebrate the periodic system in this Focus with a collection of articles that explore elements of the table, including its limits.


From the archives

Around the table

Interactive periodic table