What element has the symbol 'Sr'?

The story behind the answer

Sr is the chemical symbol for Strontium, an alkaline earth metal in Group 2 with atomic number 38. Its name comes from Strontian, a village in Scotland where it was first identified. By contrast, Selenium is Se, Sodium is Na (from Latin natrium), and “Scarcium” isn’t an element—Sc is Scandium.

Strontium salts produce a vivid crimson color in fireworks and signal flares and are used in ferrite magnets; the isotope Sr-90 is a radioactive fission product. Memory tip: StRontium makes StRong Red flames—so Sr = Strontium. Also note the Group 2 trend: Be, Mg, Ca, Sr, Ba, Ra largely use their first letters.