Silicium

14
Si
Gruppe
14
Periode
3
Blok
p
Protons
Electrons
Neutrons
14
14
14
General Properties
Atomnummer
14
Atommasse
28,0855
Mass Number
28
Kategori
Halvmetaller
Farve
Grå
Radioactive
Nej
From the Latin word silex, silicis, flint
Krystalstruktur
Tetrahedral Packing
History
In 1800, Sir Humphry Davy thought silica to be a compound and not an element; but in 1811, Gay Lussac and Louis Jacques Thénard probably prepared impure amorphous silicon by heating potassium with silicon tetrafluoride.

In 1824 Jöns Jakob Berzelius prepared amorphous silicon by the same general method.

Henri Deville in 1854 first prepared crystalline silicon, the second allotropic form of the element.
Elektroner i hver skal
2, 8, 4
Elektronkonfiguration
[Ne] 3s2 3p2
Si
Silicon also has the unusual property that it expands as it freezes
Physical Properties
Tilstandsform
Fast stof
Massefylde
2,3296 g/cm3
Smeltepunkt
1687,15 K | 1414 °C | 2577,2 °F
Kogepunkt
3538,15 K | 3265 °C | 5909 °F
Smeltevarme
50,2 kJ/mol
Fordampningsvarme
359 kJ/mol
Varmefylde
0,705 J/g·K
Abundance in Earth's crust
27%
Abundance in Universe
0,07%
Close
Billede akkrediteringer: Wikimedia Commons (Enricoros)
Close up photo of a piece of purified silicon
CAS Number
7440-21-3
PubChem CID Number
5461123
Atomic Properties
Atomradius
111 pm
Kovalent radius
111 pm
Elektronegativitet
1,9 (Paulings skala)
Ionization Potential
8,1517 eV
Atomic Volume
12,1 cm3/mol
Varmeledningsevne
1,48 W/cm·K
Oxidationstrin
-4, -3, -2, -1, 1, 2, 3, 4
Applications
In the form of sand and clay it is used to make concrete and brick; it is a useful refractory material for high-temperature work, and in the form of silicates it is used in making enamels, pottery, etc.

Silica, as sand, is a principal ingredient of glass.

Silicon chips are the basis of modern electronic and computing.

Silicon carbide, more commonly called carborundum is used in abrasives.
If breathed in as a fine silica/silicate dust, it may cause chronic respiratory problems
Isotoper
Stable Isotopes
28Si, 29Si, 30Si
Unstable Isotopes
22Si, 23Si, 24Si, 25Si, 26Si, 27Si, 31Si, 32Si, 33Si, 34Si, 35Si, 36Si, 37Si, 38Si, 39Si, 40Si, 41Si, 42Si, 43Si, 44Si