There are 17 rare earth elements (REEs) in all — 15 lanthanides plus yttrium and scandium. It's a fairly diverse group, with ...

The nucleus of each atom contains protons and neutrons. While the number of protons defines the element (e.g., hydrogen, carbon, etc.) and the sum of the protons and neutrons gives the atomic mass, ...

They all have a link to the periodic table, which turned 150 in 2019! Here are some fascinating elements that you may never have heard of, but definitely should. Krypton derives from the Greek ...