Today, the periodic table is organized by atomic number, which is the number of protons in the nucleus. But they didn’t know about protons then, so they organized everything by atomic weight.

Of course, that hasn’t stopped the table from being reimagined many times. Most recently, designer Alison Haigh created this minimalist periodic table, built less for understanding the nature of ...

In the late 1920s, Janet turned his perceptive powers to the chemical elements. He designed various new versions of the periodic table. Unlike most other tables constructed before then, his ...

Physicists have filled in some longtime blank spaces on the periodic table, calculating electron affinities of the lanthanides, a series of 15 elements known as rare earths.

Free interactive and download to print GCSE Chemistry flashcards to help prepare for your GCSE exams. Revise topics such as atoms, elements and compounds, mixtures, atomic structure, Mendeleev's ...