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Si Silicon
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

14
Si
Silicon
Element 14 of Periodic table is Silicon with atomic number 14, atomic weight 28.0855. Silicon, symbol Si, has a Tetrahedral Packing structure and Gray color. Silicon is a Metalloid element. It is part of group 14 (carbon family). Know everything about Silicon Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
14 Si - Silicon | SchoolMyKids

Silicon is a chemical element with symbol Si and atomic number 14. It is a tetravalent Metalloid, more reactive than germanium, the Metalloid directly below it in the table. Controversy about silicon's character dates to its discovery.

It belongs to group 14 of the periodic table having trivial name tetrels, crystallogens. It got its trivial name from tetrels from Greek tetra (four, IV).

Silicon Facts

Read key information and facts about element Silicon

NameSilicon
Atomic Number14
Atomic SymbolSi
Atomic Weight28.0855
PhaseSolid
ColorGray
Appearancecrystalline, reflective with bluish-tinged faces
ClassificationMetalloid
Group in Periodic Table14
Group Namecarbon family
Period in Periodic Tableperiod 3
Block in Periodic Tablep -block
Electronic Configuration[Ne] 3s2 3p2
Electronic Shell Structure (Electrons per shell)2, 8, 4
Melting Point1687 K
Boiling Point3173 K
CAS NumberCAS7440-21-3
Neighborhood Elements
123456789101112131415161718
1
1
H
Hydrogen
1.008

Atomic #

Electronic Shell #

Symbol
Name
Atomic Weight
HGas
HgLiquid
CSolid
Metals
Metalloids
NonMetals
Alkali metals
Alkali earth metals
Lanthanoids
Transition metals
Post-transition metals
Other nonmetals
Halogens
Nobel gas
Actinoids
2
He
Helium
4.003
2
3
Li
Lithium
6.941
4
Be
Beryllium
9.012
5
B
Boron
10.811
6
C
Carbon
12.011
7
N
Nitrogen
14.007
8
O
Oxygen
15.999
9
F
Fluorine
18.998
10
Ne
Neon
20.180
3
11
Na
Sodium
22.990
12
Mg
Magnesium
24.305
13
Al
Aluminium
26.982
14
Si
Silicon
28.085
15
P
Phosphorus
30.974
16
S
Sulfur
32.065
17
Cl
Chlorine
35.453
18
Ar
Argon
39.948
4
19
K
Potassium
39.098
20
Ca
Calcium
40.078
21
Sc
Scandium
44.956
22
Ti
Titanium
47.867
23
V
Vanadium
50.941
24
Cr
Chromium
51.996
25
Mn
Manganese
54.938
26
Fe
Iron
55.845
27
Co
Cobalt
58.933
28
Ni
Nickel
58.693
29
Cu
Copper
63.546
30
Zn
Zinc
65.409
31
Ga
Gallium
69.723
32
Ge
Germanium
72.640
33
As
Arsenic
74.922
34
Se
Selenium
78.960
35
Br
Bromine
79.904
36
Kr
Krypton
83.798
5
37
Rb
Rubidium
85.468
38
Sr
Strontium
87.620
39
Y
Yttrium
88.906
40
Zr
Zirconium
91.224
41
Nb
Niobium
92.906
42
Mo
Molybdenum
95.940
43
Tc
Technetium
98
44
Ru
Ruthenium
101.070
45
Rh
Rhodium
102.906
46
Pd
Palladium
106.420
47
Ag
Silver
107.868
48
Cd
Cadmium
112.411
49
In
Indium
114.818
50
Sn
Tin
118.710
51
Sb
Antimony
121.760
52
Te
Tellurium
127.600
53
I
Iodine
126.904
54
Xe
Xenon
131.293
6
55
Cs
Cesium
132.905
56
Ba
Barium
137.327
57 - 71
La - Lu
Lanthanides
72
Hf
Hafnium
178.490
73
Ta
Tantalum
180.948
74
W
Tungsten
183.840
75
Re
Rhenium
186.207
76
Os
Osmium
190.230
77
Ir
Iridium
192.217
78
Pt
Platinum
195.078
79
Au
Gold
196.967
80
Hg
Mercury
200.590
81
Tl
Thallium
204.383
82
Pb
Lead
207.200
83
Bi
Bismuth
208.980
84
Po
Polonium
209
85
At
Astatine
210
86
Rn
Radon
222
7
87
Fr
Francium
223
88
Ra
Radium
226
89 - 103
Ac - Lr
Actinides
104
Rf
Rutherfordium
261
105
Db
Dubnium
262
106
Sg
Seaborgium
266
107
Bh
Bohrium
264
108
Hs
Hassium
277
109
Mt
Meitnerium
268
110
Ds
Darmstadtium
281
111
Rg
Roentgenium
272
112
Cn
Copernicium
285
113
Nh
Nihonium
284
114
Fl
Flerovium
289
115
Mc
Moscovium
288
116
Lv
Livermorium
292
117
Ts
Tennessine
294
118
Og
Oganesson
294
Lanthanides
57
La
Lanthanum
138.905
58
Ce
Cerium
140.116
59
Pr
Praseodymium
140.908
60
Nd
Neodymium
144.240
61
Pm
Promethium
145
62
Sm
Samarium
150.360
63
Eu
Europium
151.964
64
Gd
Gadolinium
157.250
65
Tb
Terbium
158.925
66
Dy
Dysprosium
162.500
67
Ho
Holmium
164.930
68
Er
Erbium
167.259
69
Tm
Thulium
168.934
70
Yb
Ytterbium
173.040
71
Lu
Lutetium
174.967
Actinides
89
Ac
Actinium
227
90
Th
Thorium
232.038
91
Pa
Protactinium
231.036
92
U
Uranium
238.029
93
Np
Neptunium
237
94
Pu
Plutonium
244
95
Am
Americium
243
96
Cm
Curium
247
97
Bk
Berkelium
247
98
Cf
Californium
251
99
Es
Einsteinium
252
100
Fm
Fermium
257
101
Md
Mendelevium
258
102
No
Nobelium
259
103
Lr
Lawrencium
262

How to Locate Silicon on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 14 to find Silicon on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Silicon on periodic table look for cross section of group 14 and period 3 in the modern periodic table.

Silicon History

The element Silicon was discovered by J. Berzelius in year 1823 in Sweden. Silicon was first isolated by J. Berzelius in 1823. Silicon derived its name from the Latin silex, 'flint' (originally silicium).

Humphry Davy thought in 1800 that silica was a compound, not an element, and in 1808 suggested the present name. In 1811 Louis-Joseph Gay-Lussac and Louis-Jacques Thénard probably prepared impure silicon, but Berzelius is credited with the discovery for obtaining the pure element in 1823.

Silicon Presence: Abundance in Nature and Around Us

The table below shows the abundance of Silicon in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.

 ppb by weight (1ppb =10^-7 %)ppb by atoms (1ppb =10^-7 %)
Abundance in Universe70000030000
Abundance in Sun90000040000
Abundance in Meteorites140000000100000000
Abundance in Earth's Crust270000000200000000
Abundance in Oceans1000220
Abundance in Humans26000058000

Crystal Structure of Silicon

The solid state structure of Silicon is Tetrahedral Packing.

The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.

Unit Cell Parameters

The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)

abc
543.09 pm543.09 pm543.09 pm

and the angles between them Lattice Angles (alpha, beta and gamma).

alphabetagamma
π/2 π/2 π/2

The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.

The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.

Space Group NameFd_ 3m 14 Si Silicon - Crystal Structure | SchoolMyKids
Oxidation StatesSpace Group Number227
Crystal StructureTetrahedral Packing

Silicon Atomic and Orbital Properties

Silicon atoms have 14 electrons and the electronic shell structure is [2, 8, 4] with Atomic Term Symbol (Quantum Numbers) 3P0.

Atomic Number14
Number of Electrons (with no charge)14
Number of Protons14
Mass Number28
Number of Neutrons14
Shell structure (Electrons per energy level)2, 8, 4
Electron Configuration[Ne] 3s2 3p2
Valence Electrons3s2 3p2
Valence (Valency)4
Main Oxidation States-4, 4
Oxidation States-4, -3, -2, -1, 0, 1, 2, 3, 4
Atomic Term Symbol (Quantum Numbers)3P0

Bohr Atomic Model of Silicon - Electrons per energy level

14 Si Silicon - Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Silicon - neutral Silicon atom

Abbreviated electronic configuration of Silicon

The ground state abbreviated electronic configuration of Neutral Silicon atom is [Ne] 3s2 3p2. The portion of Silicon configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ne]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 3s2 3p2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Silicon

Complete ground state electronic configuration for the Silicon atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s2 3p2

Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.

  • As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
  • The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
  • Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
  • Electron configuration of Silicon
    Atomic Structure of Silicon

    Silicon atomic radius is 111 pm, while it's covalent radius is 111 pm.

    Atomic Radius Calculated

    111 pm (1.11 Å)

    Atomic Radius Empirical

    110 pm (1.1 Å)

    Atomic Volume12.054 cm3/mol
    Covalent Radius111 pm (1.11 Å)
    Van der Waals Radius210 pm
    Neutron Cross Section171
    Neutron Mass Absorption 0.0002

    Atomic Spectrum of Silicon

    Atomic Spectrum of Silicon | SchoolMyKids

    Silicon Chemical Properties: Silicon Ionization Energies and electron affinity

    The electron affinity of Silicon is 133.6 kJ/mol.

    Valence4
    Electronegativity1.9
    ElectronAffinity133.6 kJ/mol

    Ionization Energy of Silicon

    Refer to table below for Ionization energies of Silicon

    Ionization energy numberEnthalpy - kJ/mol
    1st786.5
    2nd1577.1
    3rd3231.6
    4th4355.5
    5th16091
    6th19805
    7th23780
    8th29287
    9th33878
    10th38726
    11th45962
    12th50502
    13th235196
    14th257923

    Silicon Physical Properties

    Refer to below table for Silicon Physical Properties

    Density2.33 g/cm3(when liquid at m.p density is $2.57 g/cm3)
    Molar Volume12.054 cm3/mol

    Elastic Properties

    Young Modulus47
    Shear Modulus-
    Bulk Modulus 100 GPa
    Poisson Ratio-

    Hardness of Silicon - Tests to Measure of Hardness of Element

    Mohs Hardness6.5 MPa
    Vickers Hardness-
    Brinell Hardness-

    Silicon Electrical Properties

    Silicon is Conductor of electricity. Refer to table below for the Electrical properties ofSilicon

    Electrical Conductivity1000 S/m
    Resistivity0.001 m Ω
    Superconducting Point-

    Silicon Heat and Conduction Properties

    Thermal Conductivity150 W/(m K)
    Thermal Expansion0.0000026 /K

    Silicon Magnetic Properties

    Magnetic TypeDiamagnetic
    Curie Point-
    Mass Magnetic Susceptibility-1.6e-9 m3/kg
    Molar Magnetic Susceptibility-4.49e-11 m3/mol
    Volume Magnetic Susceptibility-0.00000373

    Optical Properties of Silicon

    Refractive Index-

    Acoustic Properties of Silicon

    Speed of Sound2200 m/s

    Silicon Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Silicon

    Melting Point1687 K (1413.85°C, 2576.93 °F)
    Boiling Point3173 K (2899.85°C, 5251.73 °F)
    Critical Temperature-
    Superconducting Point-

    Enthalpies of Silicon

    Heat of Fusion50.2 kJ/mol
    Heat of Vaporization359 kJ/mol
    Heat of Combustion-9055 J/(kg K)

    Silicon Isotopes - Nuclear Properties of Silicon

    Silicon has 23 isotopes, with between 22 and 44 nucleons. Silicon has 3 stable naturally occuring isotopes.

    Isotopes of Silicon - Naturally occurring stable Isotopes: 28Si, 29Si, 30Si.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    22Si14822Synthetic
    23Si14923Synthetic
    24Si141024Synthetic
    25Si141125Synthetic
    26Si141226Synthetic
    27Si141327Synthetic
    28Si14142892.2297%Stable
    29Si1415294.6832%StableN/A
    30Si1416303.0872%StableN/A
    31Si141731Synthetic
    32Si141832Synthetic
    33Si141933Synthetic
    34Si142034Synthetic
    35Si142135Synthetic
    36Si142236Synthetic
    37Si142337Synthetic
    38Si142438Synthetic
    39Si142539Synthetic
    40Si142640Synthetic
    41Si142741Synthetic
    42Si142842Synthetic
    43Si142943Synthetic
    44Si143044Synthetic

    Regulatory and Health - Health and Safety Parameters and Guidelines

    Database Search

    List of unique identifiers to search the element in various chemical registry databases

    DatabaseIdentifier number
    CAS Number - Chemical Abstracts Service (CAS)CAS7440-21-3
    RTECS NumberRTECSVW0400000
    CID Number CID5461123
    Gmelin Number-
    NSC Number-