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 ...

The modern periodic table, arranged in rows and columns, was first introduced by Dmitri Mendeleev in 1869. At the time, it included the known elements and their properties, but Mendeleev predicted ...

The ions formed have a full outer electron shell, so are very stable. See the study guide on groups in the periodic table for more information.

Accompanying Lesson Plan: Lesson 3.2: Finding Volume—The Water Displacement Method The chart shows that atomic size and mass for the first 20 elements in the periodic table. The size of the atoms and ...