Calcium: properties, sources, roles, and safety

Classification as alkaline earth metal

Calcium is classified as an alkaline earth metal because it belongs to Group 2 of the periodic table. Like other Group 2 elements (especially strontium, barium, and radium), it has two valence electrons in the outer s-orbital, which are very easily lost in chemical reactions. As a result, calcium almost always forms a divalent (Ca2+) ion with a stable noble-gas electron configuration (argon). In its compounds, calcium is therefore typically found in ionic forms. The article also notes that while lighter Group 2 elements such as beryllium and magnesium are sometimes included, they differ significantly in physical and chemical behavior, which is why the traditional definition of “alkaline earth metal” often excludes them.

0/2 modes complete

Electron configuration and valence behavior

0/2 modes complete