Silicon (Si) ❍｜appendage｜___｜20260628174208-01-•

Silicon	…
Pronunciation	• /ˈsɪləkən/ (SIL-ə-kən) • /ˈsɪləkɒn/ (SIL-ə-kon)
Allotropes	see Allotropes of silicon
Appearance	crystalline, reflective with bluish-tinged faces
Standard atomic weight A ${}_r$ °(Si)	…
	• [28.084 , 28.086] 1 • 28.085 ± 0.001 (abridged) 2
Silicon in the periodic table	…
C ↑ Si ↓ Ge aluminium ← silicon → phosphorus	…
Atomic number (Z)	14
Group	group 14 (carbon group)
Period	period 3
Block	p-block
Electron configuration	[Ne] 3s${}^2$ 3p${}^2$
Electrons per shell	2, 8, 4
Physical properties	…
Phase at STP	solid
Melting point	1687 K ​(1414 °C, ​2577 °F)
Boiling point	3538 K ​(3265 °C, ​5909 °F)
Density (at 20° C)	2.329085 g/cm${}^3$3
when liquid (at m.p.)	2.57 g/cm${}^3$
Heat of fusion	50.21 kJ/mol
Heat of vaporization	383 kJ/mol
Molar heat capacity	19.789 J/(mol·K)
Specific heat capacity	704.611 J/(kg·K)
Vapor pressure	…
Atomic properties	…
Oxidation states	common: −4, +4 −3,4 −2,4 −1,4 0,5 +1,46 +2,4 +34
Electronegativity	Pauling scale: 1.90
Ionization energies	• 1st: 786.5 kJ/mol • 2nd: 1577.1 kJ/mol • 3rd: 3231.6 kJ/mol • (more)
Atomic radius	empirical: 111 pm
Covalent radius	111 pm
Van der Waals radius	210 pm
Spectral lines of silicon	…
Other properties	…
Natural occurrence	primordial
Crystal structure	​face-centered diamond-cubic (cF8)
Lattice constant	a = 543.0986 pm (at 20 °C)3
Thermal expansion	2.556×10${}^{-6}$/K (at 20 °C)3
Thermal conductivity	149 W/(m⋅K)
Electrical resistivity	2.3×10${}^3$ Ω⋅m (at 20 °C)7
Band gap	1.12 eV (at 300 K)
Magnetic ordering	diamagnetic8
Molar magnetic susceptibility	−3.9×10${}^{-6}$ cm${}^3$/mol (298 K)9
Young’s modulus	130–188 GPa10
Shear modulus	51–80 GPa10
Bulk modulus	97.6 GPa10
Speed of sound thin rod	8433 m/s (at 20 °C)
Poisson ratio	0.064–0.2810
Mohs hardness	6.5
CAS Number	7440-21-3
History	…
Naming	after Latin silex or silicis, meaning ‘flint’
Prediction	Antoine Lavoisier (1787)
Discovery and first isolation	Jöns Jacob Berzelius1112 (1823)
Named by	Thomas Thomson (1817)
Isotopes of silicon	…

Silicon,${}_{14}$ Si

(echo:: @ ᯤ)

Footnotes

1. “Standard Atomic Weights: Silicon”. CIAAW. 2009. ↩

2. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). “Standard atomic weights of the elements 2021 (IUPAC Technical Report)”. Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075. ↩

3. Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9. ↩ ↩² ↩³

4. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 28. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

5. “New Type of Zero-Valent Tin Compound”. Chemistry Europe. 27 August 2016. ↩

6. Ram, R. S.; et al. (1998). “Fourier Transform Emission Spectroscopy of the A2D–X2P Transition of SiH and SiD” (PDF). J. Mol. Spectr. 190 (2): 341–352. doi:10.1006/jmsp.1998.7582. PMID 9668026. ↩

7. Eranna, Golla (2014). Crystal Growth and Evaluation of Silicon for VLSI and ULSI. CRC Press. p. 7. ISBN 978-1-4822-3281-3. ↩

8. Magnetic susceptibility of the elements and inorganic compounds, in Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0486-5. ↩

9. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4. ↩

10. Hopcroft, Matthew A.; Nix, William D.; Kenny, Thomas W. (2010). “What is the Young’s Modulus of Silicon?”. Journal of Microelectromechanical Systems. 19 (2): 229. doi:10.1109/JMEMS.2009.2039697. ↩ ↩² ↩³ ↩⁴

11. Weeks, Mary Elvira (1932). “The discovery of the elements: XII. Other elements isolated with the aid of potassium and sodium: beryllium, boron, silicon, and aluminum”. Journal of Chemical Education. 9 (8): 1386–1412. Bibcode:1932JChEd…9.1386W. doi:10.1021/ed009p1386. ↩

12. Voronkov, M. G. (2007). “Silicon era”. Russian Journal of Applied Chemistry. 80 (12): 2190. doi:10.1134/S1070427207120397. ↩