Strontium

Alkaline earth metal · atomic number 38

3887.621SrStrontiumSolidAlkaline earth metal

Strontium is a chemical element with symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when it is exposed to air.

Properties of Strontium

Element category	Alkaline earth metal
Atomic number	38
Atomic mass	87.621 u
Phase at STP	Solid
Group	2
Period	5
Block	s
Electron configuration	[Kr] 5s2
Electrons per shell	2, 8, 18, 8, 2
Electronegativity (Pauling)	0.95
Melting point	1050 K (777 °C)
Boiling point	1650 K (1377 °C)
Density	2.64 g/cm3
Discovered by	William Cruickshank (chemist)

← Rubidium · Periodic table · Yttrium → Y

About the alkaline earth metal group

Reactive group-2 metals a step calmer than the alkalis: magnesium, calcium and the structural and biological workhorses among them.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Strontium

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🧪 Reactive nonmetal

11 elements: Elements that readily gain or share electrons — the building blocks of water, air, living tissue and most organic chemistry.

🧪 Noble gas

6 elements: Full outer electron shells make these gases almost inert: they barely react, glow in discharge lamps and are used to create unreactive atmospheres.

🧪 Alkali metal

6 elements: Soft, wildly reactive metals of group 1 — they fizz in water and never occur pure in nature. Lithium, sodium, potassium and friends.

🧪 Alkaline earth metal

6 elements: Reactive group-2 metals a step calmer than the alkalis: magnesium, calcium and the structural and biological workhorses among them.

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35 elements: The dense, strong, catalytic heart of the table — iron, copper, gold, titanium — responsible for most of metallurgy, jewellery and industry.

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15 elements: Mostly radioactive, heavy metals — several made only in reactors — whose fission powers nuclear energy and weapons.

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