Sr
Strontium · element 38
Alkaline Earth Metal · Solid at room temperature
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.
Key facts
Atomic mass
87.621 u
how heavy one atom is
Phase (room temp.)
Solid
Density
2.64 g/cm³
how tightly packed it is
Melting point
1050 K (777 °C)
when solid turns to liquid
Boiling point
1650 K (1377 °C)
when liquid turns to gas
Period
5
its row in the periodic table
Group
2
its column in the periodic table
Block
S-block
the neighbourhood it lives in
Electronegativity
0.95
how strongly it pulls electrons
Electron configuration
[Kr] 5s2
where its electrons live
Shells
2 · 8 · 18 · 8 · 2
electrons in each layer, inside to out
Discovered by
William Cruickshank (chemist)
who found it
Source: Wikipedia