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Silicon |
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Pronunciation | (SIL-ik-ən) |
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Appearance | crystalline, reflective wi bluish-tinged faces |
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Standard atomic weight Ar, std(Si) | [7001280840000000000♠28.084, 7001280860000000000♠28.086] conventional: 7001280850000000000♠28.085 |
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Silicon in the periodic cairt |
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Atomic nummer (Z) | 14 |
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Group | group 14 (caurbon group) |
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Period | period 3 |
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Block | p-block |
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Element category | Metalloid |
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Electron confeeguration | [Ne] 3s2 3p2 |
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Electrons per shell | 2, 8, 4 |
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Pheesical properties |
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Phase at STP | solit |
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Meltin pynt | 1687 K (1414 °C, 2577 °F) |
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Bylin pynt | 3538 K (3265 °C, 5909 °F) |
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Density (near r.t.) | 2.3290 g/cm3 |
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when liquid (at m.p.) | 2.57 g/cm3 |
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Heat o fusion | 50.21 kJ/mol |
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Heat o vapourisation | 359 kJ/mol |
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Molar heat capacity | 19.789 J/(mol·K) |
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Vapour pressur
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
1908 |
2102 |
2339 |
2636 |
3021 |
3537 |
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Atomic properties |
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Oxidation states | −4, −3, −2, −1, 0,[1] +1,[2] +2, +3, +4 (an amphoteric oxide) |
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Electronegativity | Pauling scale: 1.90 |
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Ionisation energies | |
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Atomic radius | empirical: 111 pm |
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Covalent radius | 111 pm |
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Van der Waals radius | 210 pm |
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Spectral lines o silicon |
Ither properties |
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Naitural occurrence | primordial |
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Creestal structur | diamond cubic |
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Speed o soond thin rod | 8433 m/s (at 20 °C) |
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Thermal expansion | 2.6 µm/(m·K) (at 25 °C) |
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Thermal conductivity | 149 W/(m·K) |
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Electrical resistivity | 103[3] Ω·m (at 20 °C) |
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Magnetic orderin | diamagnetic[4] |
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Young's modulus | 130-188[5] GPa |
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Shear modulus | 51-80[5] GPa |
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Bulk modulus | 97.6[5] GPa |
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Poisson ratio | 0.064 - 0.28[5] |
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Mohs haurdness | 7 |
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CAS Nummer | 7440-21-3 |
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History |
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Prediction | Antoine Lavoisier (1787) |
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Diskivery | Jöns Jacob Berzelius[6][7] (1823) |
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First isolation | Jöns Jacob Berzelius (1823) |
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Named by | Thomas Thomson (1817) |
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Main isotopes o silicon |
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Isotope |
Abundance |
Hauf-life (t1/2) |
Decay mode |
Product |
28Si |
92.23% |
stable |
29Si |
4.67% |
stable |
30Si |
3.1% |
stable |
32Si |
trace |
153 y |
β− |
32P |
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| references |