Strontium

Element 38 on the periodic table, symbol Sr, group 2, period 5.

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

Atomic Number: 38
Atomic Mass: 87.6210 u
Group: 2
Period: 5
Block: s-block
Category: Alkaline Earth Metal
State at 25 °C: Solid
Melting Point: 1,050 K · 776.9 °C
Boiling Point: 1,650 K · 1,376.9 °C
Density: 2.64 g/cm³
Atomic Radius: 200 pm
Electronegativity: 0.95
Oxidation States: +2
Abundance in Crust: 370 mg/kg
Discovered: 1790
Discovered By: William Cruickshank (chemist)

Electron Configuration

[Kr] 5s2

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2

Ionisation Energies (kJ/mol)

1. 549.5
2. 1,064.2
3. 4,138
4. 5,500
5. 6,910
6. 8,760
7. 10,230
8. 11,800

Elements near Strontium

Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.