Germanium

32
Ge
Group
14
Period
4
Block
p
Protons
Electrons
Neutrons
32
32
41
General Properties
Atomic Number
32
Atomic Weight
72.63
Mass Number
73
Category
Metalloids
Color
Gray
Radioactive
No
From the Latin word Germania, Germany
Crystal Structure
Face Centered Cubic
History
In 1869, Dmitri Mendeleev predicted its existence and some of its properties based on its position on his periodic table and called the element eka-silicon.

In 1886, Clemens Winkler found the new element along with silver and sulfur, in a rare mineral called argyrodite.

The first silicon-germanium alloys were obtained in 1955.
Electrons per shell
2, 8, 18, 4
Electron Configuration
[Ar] 3d10 4s2 4p2
Ge
Germanium and the oxide are transparent to infrared radiation
Physical Properties
Phase
Solid
Density
5.323 g/cm3
Melting Point
1211.4 K | 938.25 °C | 1720.85 °F
Boiling Point
3106.15 K | 2833 °C | 5131.4 °F
Heat of Fusion
31.8 kJ/mol
Heat of Vaporization
334 kJ/mol
Specific Heat Capacity
0.32 J/g·K
Abundance in Earth's crust
0.00014%
Abundance in Universe
0.00002%
Ultrapure
Image Credits: Images-of-elements
Ultrapure chunk of polycrystalline germanium
CAS Number
7440-56-4
PubChem CID Number
6326954
Atomic Properties
Atomic Radius
122 pm
Covalent Radius
122 pm
Electronegativity
2.01 (Pauling scale)
Ionization Potential
7.8994 eV
Atomic Volume
13.6 cm3/mol
Thermal Conductivity
0.599 W/cm·K
Oxidation States
-4, 1, 2, 3, 4
Applications
The most common use of germanium is as a semiconductor in electronics.

Germanium is used in transistors and in integrated circuits.

It is used as an alloying agent and as a catalyst.

It is also used in infrared spectroscopes and infrared detectors.
Germanium is not known to be toxic
Isotopes
Stable Isotopes
70Ge, 72Ge, 73Ge, 74Ge
Unstable Isotopes
58Ge, 59Ge, 60Ge, 61Ge, 62Ge, 63Ge, 64Ge, 65Ge, 66Ge, 67Ge, 68Ge, 69Ge, 71Ge, 75Ge, 76Ge, 77Ge, 78Ge, 79Ge, 80Ge, 81Ge, 82Ge, 83Ge, 84Ge, 85Ge, 86Ge, 87Ge, 88Ge, 89Ge