Symbol: Sr
Atomic number: 38
Atomic weight: 87.62
Soft yellowish metallic element, belongs to group 2 of the periodic
table. Highly reactive chemically. Sr-90 is present in radioactive fallout and has a half-life of 28 years. Discovered in 1798 by Klaproth and Hope, isolated in 1808 by Humphry Davy.