G

Germanium

IUPAC: Germanium

Ge Elements CAS 7440-56-4
Quick Reference
Formula / NotationGe
CAS Number7440-56-4
Molecular Weight72.63
Melting Point938.3
Boiling Point2833.0
Density5.32
SolubilityInsoluble in water
AppearanceLustrous, hard, greyish-white metalloid
Also Known AsGe, germanium element
CategoryElements

What is Germanium?

Germanium is a lustrous, hard metalloid, atomic number 32. Its existence was predicted by Mendeleev (as eka-silicon) before its discovery in 1886. Important semiconductor material in early transistors. Now mainly used in optical fibres and infrared optics.

Formula & Notation

Ge

IUPAC Name: Germanium

Other Names / Synonyms: Ge, germanium element

Properties & Characteristics

Atomic number: 32. Atomic mass: 72.640 g/mol. Period 4, Group 14 (metalloid). Melting point: 938.3 C. Boiling point: 2833 C. Density: 5.32 g/cm3. Band gap: 0.67 eV (semiconductor). Electronegativity: 2.01. Five stable isotopes.

Physical Data

PropertyValue
Melting Point938.3
Boiling Point2833.0
Density5.32
Molecular Weight72.63
SolubilityInsoluble in water
AppearanceLustrous, hard, greyish-white metalloid

Uses & Applications

Optical fibres (GeO2 increases refractive index). Infrared optics and night vision (transparent to IR). Semiconductor devices (historical - first transistors). Solar cells (space applications). Polymerisation catalyst (PET production). Germanium tetrachloride precursor.

Safety Information

Germanium metal: low acute toxicity. Germanium tetrachloride: corrosive, reacts with moisture to form HCl. Germane (GeH4): flammable and toxic gas. Organic germanium compounds: low toxicity but some concerns about renal toxicity with excessive intake.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Germanium
Formula Ge
CAS Number 7440-56-4
Molecular Weight 72.63
Category Elements
Synonyms Ge, germanium element

Frequently Asked Questions

Germanium is a lustrous, hard metalloid, atomic number 32. Its existence was predicted by Mendeleev (as eka-silicon) before its discovery in 1886. Important semiconductor material in early transistors. Now mainly used in optical fibres and infrared optics.

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