The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

You may use table navigation commands for the screen reader of your choice. The Periodic Table of Elements. Each entry contains the atomic number, chemical symbol, and atomic mass to two decimal ...

The first 94 are found in nature ... the behavior of the elements based on the number of protons in the atom. For the world at large, an "element table" makes more sense. See atom.

Such an element, neptunium or element 93, was identified in 1940, and in that same year Seaborg was one of a team at Berkeley that created the next in line: plutonium, element 94. The challenge was to ...

Plutonium's in a part of the periodic table called the actinide series alongside its neighbours thorium and protoactinium. Seaborg christened the actinides, rearranging the periodic table in the ...