Periodic Table

Germanium

Metalloid

Quick Facts about Germanium

Ga
  • solid- state of matter at room temperature
  • Stable- has at least one stable isotope
  • +4, +2- common oxidation states in compounds
  • DIA- crystal structure, atomic arrangement in solid form
As

Germanium (Ge) is element 32 on the periodic table. Atomic mass of Ge: 72.6300 u. Ge is in period 4, group 14. Melting point of Ge: 1211.40 K.Density of Ge: 5.32 g/cm³.

Why Germanium Matters

Germanium in everyday life and industry

In Your Home

  • Fiber optic cables use germanium-doped glass for better light transmission
  • Infrared night-vision equipment uses germanium lenses
  • Early transistors were made from germanium before silicon dominated

Industry Uses

ChemicalPolymerization catalysts for PET plastic bottles contain germanium

In Your Body

✗ Not essential

Germanium has no proven essential biological role. Germanium supplements are marketed but not scientifically proven beneficial.

Safety: Organic germanium compounds have caused kidney damage and deaths. The element itself has low toxicity.

Discovery of Germanium

Discovered by Clemens Winkler in Germany, 1886

Name origin: Latin: Germania (Germany).

History & Events

1886
Named after Germany, home of discoverer Clemens Winkler
1886
Discovered in 1886, fulfilling Mendeleev's prediction of 'eka-silicon'
1947
First semiconductor used in electronic devices (1947 transistor)
1886
Silicon later replaced germanium in most applications

About Germanium

Lustrous hard metalloid element, belongs to group 14 of the periodic table. Forms a large number of organometallic compounds. Predicted by Mendeleev in 1871, it was actually found in 1886 by Winkler.

Atomic Properties of Ge

Atomic Number of Ge
32
Atomic Mass of Ge
72.6300 u
Electron Configuration
[Ar] 3d10 4s2 4p2
Electronegativity
2.01
Block
p-block
Group
14
Period
4

Physical Properties of Ge

Phase (STP)
solid
Melting Point of Ge
1211.40 K
Boiling Point of Ge
3106.00 K
Density of Ge
5.3230 g/cm3

Thermal Properties

Heat of Fusion
36.80 kJ/mol
Heat of Vaporization
328.00 kJ/mol
Specific Heat
0.32 J/g·K
Molar Heat Capacity
23.22 J/mol·K
Thermal Conductivity
60.20 W/m·K

Atomic Radii

Calculated
125 pm
Covalent
121 pm
Van der Waals
211 pm
Metallic
124 pm

Common Misconceptions

Wrong:Germanium supplements are not proven health treatments.
Correct:Some have caused deaths
Wrong:Germanium is still the main semiconductor.
Correct:Silicon replaced it decades ago
Wrong:Germanium is particularly rare.
Correct:It's about as abundant as tin

Isotopes of Germanium

Germanium has 5 naturally occurring isotopes, plus 1 notable radioactive isotope.

IsotopeAtomic Mass (u)AbundanceHalf-LifeDecay Mode
6832Ge (Ge-68)Germanium-68 isotope67.9280940%270.95 daysEC
7032Ge (Ge-70)Germanium-70 isotope69.9242487520.57%
7232Ge (Ge-72)Germanium-72 isotope71.9220758327.45%
7332Ge (Ge-73)Germanium-73 isotope72.923458967.750%
7432Ge (Ge-74)Germanium-74 isotope73.9211777636.50%
7632Ge (Ge-76)Germanium-76 isotope75.921402737.730%

Data source: NIH PubChem (aggregated from IUPAC, NIST)

Isotope Applications

Isotopes of Germanium have important real-world applications in science and industry.

Medical Applications

68Ge is used to calibrate positron emission tomography (PET) scanners, which have been used for medical diagnostic procedures [268].

Abundance

Earth's Crust
1.5 mg/kg
Seawater
5.00×10-5 mg/L

Uses

Widely used in semiconductors. It is a good semiconductor when combined with tiny amounts of phosphorus, arsenic, gallium, and antimony.

Sources

Obtained from refining copper, zinc and lead.

Geochemistry

Goldschmidt
chalcophile

Test Your Knowledge

Loading quiz...