Symbol

Sr

Atomic Number

38

Atomic Mass

87.62

Family

Group 2 (Iia) Alkaline Earth Metal Pronunciation

STRONT-she-um

Overview

Strontium is a member of the alkaline earth metals. The alkaline earth metals make up Group 2 (IIA) of the periodic table. The periodic table is a chart that shows how chemical elements are related to one another. Other alkaline metals include beryllium, magnesium, calcium, barium, and radium. Strontium occupies a middle position in the family. Chemically, it is more active than calcium or magnesium, above it in the periodic table. But it is less active than barium, below it in Group 2.

The existence of strontium was first recognized in 1790 by Irish physician Adair Crawford (1748-95). However, the element was not prepared in pure form until nearly 20 years later by English chemist Humphry Davy (1778-1829). (See sidebar on Davy in the calcium entry in Volume 1.)

By far the major use of strontium is in...