What is Germanium's atomic number?

Germanium has atomic number 32, meaning it has 32 protons in its nucleus. Its chemical symbol is Ge.

Is Germanium a metal or nonmetal?

Germanium is classified as a metalloid (or semimetal). It has a metallic luster but acts as a semiconductor, making it neither a full metal nor a nonmetal.

What is Germanium used for?

Germanium is used primarily in fiber optic cables (as GeO2 dopant), infrared optics, polyethylene terephthalate (PET) catalysts, solar cells, and night-vision devices.

What is Germanium's electron configuration?

Germanium's full electron configuration is [Ar] 3d10 4s2 4p2. It has 4 valence electrons, which is why it forms the same types of compounds as carbon and silicon.

Who discovered Germanium?

Germanium was discovered in 1886 by German chemist Clemens Winkler. It was the third element Mendeleev had predicted (as "eka-silicon"), confirming the validity of the periodic table.

Germanium is relatively rare, with a crustal abundance of about 1.5 ppm. It is recovered mainly as a by-product of zinc ore (sphalerite) smelting and coal fly ash.

Germanium Element Properties

Explore the complete physical and chemical properties of Germanium (Ge, element 32) — from its semiconductor nature to its role in fiber optics and infrared optics.

72.630

Germanium

Metalloid · Period 4 · Group 14

Melting Point

938.25 °C

Boiling Point

2833 °C

Density

5.323 g/cm³

Atomic Mass

72.630 u

Electron Shell Configuration

[Ar] 3d¹⁰ 4s² 4p²

Shells: 2, 8, 18, 4

Filter Properties

Property	Value
Element Name	Germanium
Symbol	Ge
Atomic Number	32
Atomic Mass	72.630 u
Category	Metalloid (Semiconductor)
Group	14 (IVA)
Period	4
Block	p-block
CAS Number	7440-56-4
Discovered	1886
Discovered By	Clemens Winkler
Named After	Germania (Latin for Germany)
Predicted By	Dmitri Mendeleev (as eka-silicon, 1871)
Standard State	Solid at 25 °C
Appearance	Grayish-white, lustrous, brittle solid

Property	Value
Electron Configuration	[Ar] 3d10 4s2 4p2
Electrons Per Shell	2, 8, 18, 4
Number of Protons	32
Number of Neutrons (Ge-74)	42
Number of Electrons	32
Valence Electrons	4
Oxidation States	+4 (primary), +2 (less common), -4
Electronegativity (Pauling)	2.01
Electron Affinity	119 kJ/mol
First Ionization Energy	762.2 kJ/mol
Second Ionization Energy	1537.5 kJ/mol
Third Ionization Energy	3302.1 kJ/mol
Atomic Radius (calc.)	125 pm
Covalent Radius	122 pm
Van der Waals Radius	211 pm
Stable Isotopes	Ge-70 (20.57%), Ge-72 (27.45%), Ge-73 (7.75%), Ge-74 (36.50%), Ge-76 (7.73%)

Property	Value
Melting Point	938.25 °C (1720.85 °F / 1211.40 K)
Boiling Point	2833 °C (5131 °F / 3106 K)
Density (at 25 °C)	5.323 g/cm³
Density (liquid, at m.p.)	5.60 g/cm³
Heat of Fusion	36.94 kJ/mol
Heat of Vaporization	334 kJ/mol
Specific Heat Capacity	0.320 J/(g·K)
Thermal Conductivity	60.2 W/(m·K)
Thermal Expansion	6.0 µm/(m·K) at 25 °C
Electrical Resistivity	1–500 mΩ·m (semiconductor, varies with purity)
Band Gap	0.67 eV at 25 °C
Young's Modulus	103 GPa
Bulk Modulus	75 GPa
Mohs Hardness	6.0
Crystal Structure	Diamond cubic (like silicon)
Magnetic Ordering	Diamagnetic

Property	Value
Reactivity	Low; stable in air and water at room temperature
Reaction with Water	Does not react with water; stable in steam up to ~700 °C
Reaction with Air	Forms thin native oxide (GeO2) at elevated temperatures
Reaction with Acids	Resists HCl and dilute H2SO4; dissolves in HNO3 and aqua regia
Reaction with Bases	Reacts with concentrated NaOH to form germanate ions
Common Compounds	GeO2, GeCl4, GeH4 (germane), GeS2, Ge3N4
Key Optical Use	GeO2 — optical fiber dopant and IR lens material
Key Semiconductor Use	Ge — early transistors; SiGe alloys in modern CPUs
Key Catalyst Use	GeO2 — PET polymerization catalyst
Oxidation State Range	-4, 0, +2, +4 (+4 most stable)
Amphoteric Nature	Mild; reacts with strong bases forming germanates
Toxicity	Low toxicity; certain inorganic Ge compounds are mildly toxic
Natural Occurrence	Trace element in sphalerite, argyrodite, coal fly ash (~1.5 ppm crust)
Global Production	~130 tonnes/year (by-product of zinc and coal processing)

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Summary

Germanium (Ge) is element 32 on the periodic table, a metalloid (semiconductor) in group 14, period 4. Predicted by Mendeleev as "eka-silicon" and discovered in 1886, it was one of the first semiconductor materials used in transistors. Today Germanium is critical in fiber optic cables, infrared optics, and polymerization catalysts. This reference page presents all key atomic, physical, and chemical properties in one organized view.

How it works

All Germanium property data is embedded directly in the page — no server call is needed.
Use the section tabs (Overview, Atomic, Physical, Chemical) to navigate different property groups.
Click any property row to copy its value to your clipboard.
The electron configuration diagram shows the shell distribution visually.
Use the search box to filter properties by name.

Use cases

Quick reference for students studying periodic table elements.
Verify Germanium specs during semiconductor or materials research.
Teaching aid for illustrating Mendeleev's prediction of eka-silicon.
Cross-check Germanium isotope and thermodynamic data for lab work.
Explore Germanium's role in fiber optics and infrared camera lenses.
Support chemistry homework and exam preparation.
Look up electron configuration for quantum chemistry assignments.
Identify oxidation states for inorganic synthesis planning.

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Last updated: 2026-09-30 · Reviewed by Nham Vu