Periodic System for Chemists

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Table
14
28.09

Si

Silicon

Identification

CAS Number: 7440-21-3
Discovery Year: 1824
Discoverer: Jöns Berzelius
Discovery Location: Sweden

Properties

Atomic Mass: 28.085 →Density: 2.3296 g/cm³ →
Crust Abundance: 282000 mg/kg
Crystal Structure: DIA

Atomic Dimensions

Atomic Radius: 110 pm →
Atomic Radius (Rahm): 231.99999999999997 pm
Covalent Radius: 111.00000000000001 pm →
Van der Waals Radius: 210 pm
Metallic Radius: 117 pm
Atomic Volume: 12.1 cm³/mol
Lattice Constant: 5.43 Å

Thermodynamics

Melting Point: 1683 K →Boiling Point: 2628 K →Specific Heat: 0.703 J/(g·K) →Thermal Conductivity: 149 W/(m·K) →Heat of Fusion: 50.6 kJ/mol →Heat of Vaporization: 383 kJ/mol →
Heat of Formation: 450 kJ/mol

Electronic Structure

Electron Config: [Ne] 3s2 3p2
Block: p
Period: 3 →Group: 14 →Electronegativity: 1.9 →Electron Affinity: 1.3895211 eV →
Oxidation States: -4, +2, +4

Abundance & Geochemistry

Crust Abundance: 282000 mg/kg
Sea Abundance: 2.2 mg/L
Geochemical Class: major
Goldschmidt Class: litophile

About

Silicon is a hard, brittle metalloid that is the second most abundant element in Earth's crust. It is essential to the semiconductor industry.

Isotopes

Si-28 28 92.19%
Si-29 29 4.70%
Si-30 30 3.11%

Related Elements

Category

Metalloids

Same Group

6 C Carbon32 Ge Germanium50 Sn Tin82 Pb Lead114 Fl Flerovium

Same Period

11 Na Sodium12 Mg Magnesium13 Al Aluminum15 P Phosphorus16 S Sulfur17 Cl Chlorine

Periodic Trends

Electronegativity →Atomic Radius →Density →Melting Point →

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