Os - Osmium

76
Os
Osmium

Osmium Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

Element 76 of Periodic table is Osmium with atomic number 76, atomic weight 190.23. Osmium, symbol Os, has a Simple Hexagonal structure and SlateGray color. Osmium is a Transition Metal element. It is part of group 8 (iron family). Know everything about Osmium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
76 Os - Osmium | SchoolMyKids

Osmium (from Greek osme (ὀσμή) meaning 'smell') is a chemical element with symbol Os and atomic number 76. It is a hard, brittle, bluish-white Transition Metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element, with a density of 7004225900000000000♠22.59 g/cm3.

It belongs to group 8 of the periodic table having trivial name null. You can also download Printable Periodic Table of Elements Flashcards for Osmium in a PDF format.

Osmium Facts

Read key information and facts about element Osmium

NameOsmium
Atomic Number76
Atomic SymbolOs
Atomic Weight190.23
PhaseSolid
ColorSlateGray
Appearancesilvery, blue cast
ClassificationTransition Metal
Natural OccurancePrimordial
Group in Periodic Table8
Group Nameiron family
Period in Periodic Tableperiod 6
Block in Periodic Tabled-block
Electronic Configuration[Xe] 4f14 5d6 6s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 32, 14, 2
Melting Point3306 K
Boiling Point5285 K
CAS NumberCAS7440-04-2
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
269
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 Osmium 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 76 to find Osmium 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 Osmium on periodic table look for cross section of group 8 and period 6 in the modern periodic table.

Osmium History

The element Osmium was discovered by S. Tennant in year 1803 in United Kingdom. Osmium was first isolated by S. Tennant in 1803. Osmium derived its name from the Greek osmè, meaning 'smell'.

Discovered By S. Tennant
Discovery Date 1803 in United Kingdom
First Isolation 1803
Isolated by S. Tennant

Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium.

Osmium Uses

Osmium is mainly used to make tough metal alloys. You can find it in ballpoint pen tips, record needles, electrical contacts, and other metal components where friction needs to be reduced.

Osmium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Osmium 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 Universe30.02
Abundance in Sun20.02
Abundance in Meteorites67070
Abundance in Earth's Crust1.80.2
Abundance in Oceans--
Abundance in Humans--

Crystal Structure of Osmium

The solid state structure of Osmium is Simple Hexagonal.

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
273.44 pm273.44 pm431.73 pm

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

alphabetagamma
π/2 π/2 2 π/3

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 NameP63/mmc
Space Group Number194
Crystal StructureSimple Hexagonal
Number of atoms per unit cell
76 Os Osmium - Crystal Structure | SchoolMyKids

The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.

Osmium Atomic and Orbital Properties

Osmium atoms have 76 electrons and the electronic shell structure is [2, 8, 18, 32, 14, 2] with Atomic Term Symbol (Quantum Numbers) 5D4.

Atomic Number76
Number of Electrons (with no charge)76
Number of Protons76
Mass Number190
Number of Neutrons114
Shell structure (Electrons per energy level)2, 8, 18, 32, 14, 2
Electron Configuration[Xe] 4f14 5d6 6s2
Valence Electrons5d6 6s2
Valence (Valency)6
Main Oxidation States4
Oxidation States-4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8
Atomic Term Symbol (Quantum Numbers)5D4

Bohr Atomic Model of Osmium - Electrons per energy level

76 Os Osmium Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Osmium - neutral Osmium atom

Abbreviated electronic configuration of Osmium

The ground state abbreviated electronic configuration of Neutral Osmium atom is [Xe] 4f14 5d6 6s2. The portion of Osmium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Xe]. 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 5d6 6s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Osmium

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

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d6 6s2

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 Osmium

Atomic Structure of Osmium

Osmium atomic radius is 185 pm, while it's covalent radius is 128 pm.

Atomic Radius Calculated185 pm(1.85 Å)
Atomic Radius Empirical130 pm (1.3 Å)
Atomic Volume8.421 cm3/mol
Covalent Radius128 pm (1.28 Å)
Van der Waals Radius-
Neutron Cross Section15
Neutron Mass Absorption 0.0023

Spectral Lines of Osmium - Atomic Spectrum of Osmium

A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules.

Spectral lines are the result of interaction between a quantum system and a single photon. A spectral line may be observed either as an emission line or an absorption line.

Spectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium. Several elements, including helium, thallium, and caesium, were discovered by spectroscopic means. They are widely used to determine the physical conditions of stars and other celestial bodies that cannot be analyzed by other means.

Emission spectrum of Osmium

Emission Spectrum of Osmium | SchoolMyKids

Absorption spectrum of Osmium

Absorption Spectrum of Osmium | SchoolMyKids

Osmium Chemical Properties: Osmium Ionization Energies and electron affinity

The electron affinity of Osmium is 106.1 kJ/mol.

Valence6
Electronegativity2.2
ElectronAffinity106.1 kJ/mol

Ionization Energy of Osmium

Ionization energy is the amount of energy required to remove an electron from an atom or molecule.in chemistry, this energy is expresed in kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).

Refer to table below for Ionization energies of Osmium

Ionization energy numberEnthalpy - kJ/mol
1st840
2nd1600

Osmium Physical Properties

Refer to below table for Osmium Physical Properties

Density22.59 g/cm3(when liquid at m.p density is $20 g/cm3)
Molar Volume8.421 cm3/mol

Elastic Properties

Young Modulus-
Shear Modulus222 GPa
Bulk Modulus -
Poisson Ratio0.25

Hardness of Osmium - Tests to Measure of Hardness of Element

Mohs Hardness7 MPa
Vickers Hardness-
Brinell Hardness3920 MPa

Osmium Electrical Properties

Electrical resistivity measures element's electrical resistance or how strongly it resists electric current.The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). While Electrical conductivity is the reciprocal of electrical resistivity. It represents a element's ability to conduct electric current. The SI unit of electrical conductivity is siemens per metre (S/m).

Osmium is a conductor of electricity. Refer to table below for the Electrical properties of Osmium

Electrical conductors Conductor
Electrical Conductivity12000000 S/m
Resistivity8.1e-8 m Ω
Superconducting Point0.66

Osmium Heat and Conduction Properties

Thermal Conductivity88 W/(m K)
Thermal Expansion0.0000051 /K

Osmium Magnetic Properties

Magnetic TypeParamagnetic
Curie Point-
Mass Magnetic Susceptibility6e-10 m3/kg
Molar Magnetic Susceptibility1.1e-10 m3/mol
Volume Magnetic Susceptibility0.000014

Optical Properties of Osmium

Refractive Index-

Acoustic Properties of Osmium

Speed of Sound4940 m/s

Osmium Thermal Properties - Enthalpies and thermodynamics

Refer to table below for Thermal properties of Osmium

Melting Point3306 K(3032.85 °C, 5491.130 °F)
Boiling Point5285 K(5011.85 °C, 9053.330 °F)
Critical Temperature-
Superconducting Point0.66

Enthalpies of Osmium

Heat of Fusion31 kJ/mol
Heat of Vaporization630 kJ/mol
Heat of Combustion-

Osmium Isotopes - Nuclear Properties of Osmium

Osmium has 35 isotopes, with between 162 and 196 nucleons. Osmium has 6 stable naturally occuring isotopes.

Isotopes of Osmium - Naturally occurring stable Isotopes: 184Os, 187Os, 188Os, 189Os, 190Os, 192Os.

IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
162Os7686162Synthetic
163Os7687163Synthetic
164Os7688164Synthetic
165Os7689165Synthetic
166Os7690166Synthetic
167Os7691167Synthetic
168Os7692168Synthetic
169Os7693169Synthetic
170Os7694170Synthetic
171Os7695171Synthetic
172Os7696172Synthetic
173Os7697173Synthetic
174Os7698174Synthetic
175Os7699175Synthetic
176Os76100176Synthetic
177Os76101177Synthetic
178Os76102178Synthetic
179Os76103179Synthetic
180Os76104180Synthetic
181Os76105181Synthetic
182Os76106182Synthetic
183Os76107183Synthetic
184Os761081840.02%StableN/A
185Os76109185Synthetic
186Os761101861.59%StableN/A
187Os761111871.96%StableN/A
188Os7611218813.24%StableN/A
189Os7611318916.15%StableN/A
190Os7611419026.26%Stable
191Os76115191Synthetic
192Os7611619240.78%StableN/A
193Os76117193Synthetic
194Os76118194Synthetic
195Os76119195Synthetic
196Os76120196Synthetic

Regulatory and Health - Health and Safety Parameters and Guidelines

The United States Department of Transportation (DOT) identifies hazard class of all dangerous elements/goods/commodities either by its class (or division) number or name. The DOT has divided these materials into nine different categories, known as Hazard Classes.

Flammable solids, self-reactive substances and solid desensitized explosives

NFPA 704 is a Standard System for the Identification of the Hazards of Materials for Emergency Response. NFPA is a standard maintained by the US based National Fire Protection Association.

The health (blue), flammability (red), and reactivity (yellow) rating all use a numbering scale ranging from 0 to 4. A value of zero means that the element poses no hazard; a rating of four indicates extreme danger.

NFPA Fire Rating4Flash Points below 22.8°C (73°F)
NFPA Health Rating
NFPA Reactivity Rating1 Flash Points Above 93.3°C (200°F)
NFPA Hazards
Autoignition Point-
Flashpoint-

Database Search

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

DatabaseIdentifier number
CAS Number - Chemical Abstracts Service (CAS)CAS7440-04-2
RTECS NumberRTECSRN1100000
CID Number CID23937
Gmelin Number-
NSC Number-

Compare Osmium with other elements

Compare Osmium with Group 8, Period 6 and Transition Metal elements of the periodic table.

Compare Osmium with all Group 8 elements

Compare Osmium with all Period 6 elements

Compare Osmium with all Transition Metal elements

Frequently Asked Questions (FAQ)

Find the answers to the most frequently asked questions about Osmium

The electronic configuration of Osmium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d6 6s2.

The abbreviated electronic configuration of Osmium is [Xe] 4f14 5d6 6s2. To form abbreviated notation of electronic configuration, the completely filled subshells are replaced by the noble gas of the preceding period in square brackets.

Symbol of Osmium is Os. Osmium is a chemical element with symbol Os and atomic number 76.

Osmium is a chemical element with the symbol Os and atomic number 76. Osmium is the 76 element on the periodic table. It is located in group 8 and period 6 in the modern periodic table.

The atomic number of Osmium is 76.

Osmium is of SlateGray color.

The element Osmium was discovered by S. Tennant in year 1803 in United Kingdom. Osmium was first isolated by S. Tennant in 1803.

Osmium has 6 valence electrons. Osmium has 76 electrons out of which 6 valence electrons are present in the 5d6 6s2 outer orbitals of atom.

Melting Point of Osmium is 3306 K.

Boiling Point of Osmium is 5285 K.

Melting Point of Osmium in Kelvin is 3306 K.

Boiling Point of Osmium in Kelvin is 5285 K.

Melting Point of Osmium in Celsius is 3032.85 °C.

Boiling Point of Osmium in Celsius is 5011.85 °C.

Melting Point of Osmium in Fahrenheit is 5491.13 °F.

Boiling Point of Osmium in Fahrenheit is 9053.33 °F.

The electronic configuration of Osmium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d6 6s2.

The electronic configuration of Osmium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d6 6s2.