Strontium is a chemical element. It has the chemical symbol Sr. It has the atomic number 38. It is a metal. The colour of the metal is silver-white or yellow-silver. The metal is soft, and highly reactive chemically.
In chemistry it is placed in a group of metal elements named the alkaline earth metals. Strontium has a high chemical reactivity. The metal turns yellow when exposed to air. Strontium has properties similar to those of its two vertical neighbours in the periodic table, calcium and barium.