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General | |||||||||||||||||||||||||||||||
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Name, Symbol, Number | Germanium, Ge, 32 | ||||||||||||||||||||||||||||||
Series | Metalloids | ||||||||||||||||||||||||||||||
Group, Period, Block | 14 (IVA)[?], 4 , p | ||||||||||||||||||||||||||||||
Density, Hardness | 5323 kg/m3, 6 | ||||||||||||||||||||||||||||||
Appearance | greyish white | ||||||||||||||||||||||||||||||
Atomic Properties | |||||||||||||||||||||||||||||||
Atomic weight | 72.64 amu | ||||||||||||||||||||||||||||||
Atomic radius (calc.) | 125 (125) pm | ||||||||||||||||||||||||||||||
Covalent radius | 122 pm | ||||||||||||||||||||||||||||||
van der Waals radius | no data | ||||||||||||||||||||||||||||||
Electron configuration | [Ar]3d10 4s2 4p2 | ||||||||||||||||||||||||||||||
e- 's per energy level | 2, 8, 18, 4 | ||||||||||||||||||||||||||||||
Oxidation states (Oxide) | 4 (amphoteric) | ||||||||||||||||||||||||||||||
Crystal structure | Cubic face centered | ||||||||||||||||||||||||||||||
Physical Properties | |||||||||||||||||||||||||||||||
State of matter | solid | ||||||||||||||||||||||||||||||
Melting point | 1211.4 K (1720.9 °F) | ||||||||||||||||||||||||||||||
Boiling point | 3093 K (5108 °F) | ||||||||||||||||||||||||||||||
Molar volume | 13.63 ×10-3 m3/mol | ||||||||||||||||||||||||||||||
Heat of vaporization | 330.9 kJ/mol | ||||||||||||||||||||||||||||||
Heat of fusion | 36.94 kJ/mol | ||||||||||||||||||||||||||||||
Vapor pressure | 0.0000746 Pa at 1210 K | ||||||||||||||||||||||||||||||
Speed of sound | 5400 m/s at 293.15 K | ||||||||||||||||||||||||||||||
Miscellaneous | |||||||||||||||||||||||||||||||
Electronegativity | 2.01 (Pauling scale) | ||||||||||||||||||||||||||||||
Specific heat capacity | 320 J/(kg*K) | ||||||||||||||||||||||||||||||
Electrical conductivity | 1.45 ohm | ||||||||||||||||||||||||||||||
Thermal conductivity | 59.9 W/(m*K) | ||||||||||||||||||||||||||||||
1st ionization potential | 762 kJ/mol | ||||||||||||||||||||||||||||||
2nd ionization potential | 1537.5 kJ/mol | ||||||||||||||||||||||||||||||
3rd ionization potential | 3302.1 kJ/mol | ||||||||||||||||||||||||||||||
4th ionization potential | 4411 kJ/mol | ||||||||||||||||||||||||||||||
5th ionization potential | 9020 kJ/mol | ||||||||||||||||||||||||||||||
Most Stable Isotopes | |||||||||||||||||||||||||||||||
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SI units & STP are used except where noted. |
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The alloy silicon germanide[?] (SiGe) is rapidly becoming an important semiconductor material, for use in high speed integrated circuits. Circuits utilising the properties of Si-SiGe junctions can be much faster than those using silicon alone.
Other uses:
Certain compounds of germanium have low toxicity to mammals, but have toxic effects against certain bacteria. This property makes these compounds useful as chemotherapeutic agents.
Property | Ekasilicon | Germanium |
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atomic mass | 72 | 72.59 |
density (g/cm3) | 5.5 | 5.35 |
melting point (°C) | high | 947 |
color | gray | gray |
The development of the germanium transistor opened the door to countless applications of solid-state[?] electronics. From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high purity silicon began replacing germanium in transistors, diodes, and rectifiers. Silicon has superior electrical properties, but requires much higher purity samples—a purity which could not be commercially achieved in the early days. Meanwhile, demand for germanium in fiber optics communication networks, infrared night vision[?] systems, and polymerization catalysts increased dramatically. These end uses represented 85% of worldwide germanium consumption for 2000.
Germanium is obtained commercially from zinc ore processing smelter dust and from the combustion by-products of certain coals. A large reserve of this element is therefore in coal sources.
This metaloid can be extracted from other metals by fractional distillation of its volatile tetrachloride. This technique permits the production of ultra-high purity germanium.
In 1997 the cost of germanium was about US$ 3 per gram. The yearend price for germanium in 2000 was $1,150 per kilogram.
wikipedia.org dumped 2003-03-17 with terodump