Symbol	Ge
Atomic number	32
Group	14 (Carbon group)
Period	4
Block	p
Classification	Metalloid

Appearance	Grayish-white
Color	Gray

Number of protons	32 p+
Number of neutrons	41 n0
Number of electrons	32 e-

From Wikipedia, the free encyclopediaGermanium is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Purified germanium is a semiconductor, with an appearance most similar to elemental silicon.

Phase at STP	Solid
Density	5.323 g/cm3
Atomic weight	72.6308 u

Melting point	1211.4 K 938.25 °C 1720.85 °F
Boiling point	3106 K 2832.85 °C 5131.13 °F
Heat of vaporization	334.3 kJ/mol

Electronegativity (Pauling Scale)	2.01
Electron affinity	118.935 kJ/mol
Oxidation states	−4 −3, −2, −1, 0, +1, +2, +3, +4 (an amphoteric oxide)
Ionization energies	762 kJ/mol 1537.5 kJ/mol 3302.1 kJ/mol 4411 kJ/mol 9020 kJ/mol

Electron configuration Shorthand configuration	[Ar] 3d10 4s2 4p2
Electron configuration Full configuration	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2
Electron configuration chart	1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2
Electrons per shell	2, 8, 18, 4
Valence electrons	4
Valency electrons	4,2
Bohr model	Figure: Shell diagram of Germanium (Ge) atom.
Orbital Diagram	1s 2s 2p 3s 3p 3d 4s 4p

Prediction	Dmitri Mendeleev (1869)
Discovery and first isolation	Clemens Winkler (1886)
Discovery of germanium Because it seldom appears in high concentration, germanium was discovered comparatively late in the discovery of the elements. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In his report on The Periodic Law of the Chemical Elements in 1869, the Russian chemist Dmitri Mendeleev predicted the existence of several unknown chemical elements, including one that would fill a gap in the carbon family, located between silicon and tin. Because of its position in his periodic table, Mendeleev called it ekasilicon (Es), and he estimated its atomic weight to be 70 (later 72). In 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after his country, Germany. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is also recovered commercially from silver, lead, and copper ores.

CAS Number	7440-56-4
ChemSpider ID	4885606
EC number	231-164-3
PubChem CID Number	6326954