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Hf Hafnium
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

72
Hf
Hafnium
Element 72 of Periodic table is Hafnium with atomic number 72, atomic weight 178.49. Hafnium, symbol Hf, has a Simple Hexagonal structure and Gray color. Hafnium is a Transition Metal element. It is part of group 4 (titanium family). Know everything about Hafnium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
72 Hf - Hafnium | SchoolMyKids

Hafnium is a chemical element with symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent Transition Metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1923, making it the penultimate stable element to be discovered (rhenium was identified two years later).

It belongs to group 4 of the periodic table having trivial name .

Hafnium Facts

Read key information and facts about element Hafnium

NameHafnium
Atomic Number72
Atomic SymbolHf
Atomic Weight178.49
PhaseSolid
ColorGray
Appearancesteel gray
ClassificationTransition Metal
Group in Periodic Table4
Group Nametitanium family
Period in Periodic Tableperiod 6
Block in Periodic Tabled -block
Electronic Configuration[Xe] 4f14 5d2 6s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 32, 10, 2
Melting Point2506 K
Boiling Point4876 K
CAS NumberCAS7440-58-6
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 Hafnium 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 72 to find Hafnium 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 Hafnium on periodic table look for cross section of group 4 and period 6 in the modern periodic table.

Hafnium History

The element Hafnium was discovered by D. Coster and G. von Hevesy in year 1922 in Denmark. Hafnium was first isolated by D. Coster and G. von Hevesy in 1922. Hafnium derived its name from Hafnia, the New Latin name for Copenhagen.

Georges Urbain claimed to have found the element in rare-earth residues, while Vladimir Vernadsky independently found it inorthite. Neither claim was confirmed due toWorld War I, and neither could be confirmed later, as the chemistry they reported does not match that now known for hafnium. After the war, Coster and Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon. Hafnium was the last stable element to be discovered.

Hafnium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Hafnium 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 Universe0.70.005
Abundance in Sun10.01
Abundance in Meteorites17020
Abundance in Earth's Crust3300380
Abundance in Oceans0.0080.00028
Abundance in Humans--

Crystal Structure of Hafnium

The solid state structure of Hafnium 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
319.64 pm319.64 pm505.11 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 72 Hf Hafnium - Crystal Structure | SchoolMyKids
Oxidation StatesSpace Group Number194
Crystal StructureSimple Hexagonal

Hafnium Atomic and Orbital Properties

Hafnium atoms have 72 electrons and the electronic shell structure is [2, 8, 18, 32, 10, 2] with Atomic Term Symbol (Quantum Numbers) 3F2.

Atomic Number72
Number of Electrons (with no charge)72
Number of Protons72
Mass Number178
Number of Neutrons106
Shell structure (Electrons per energy level)2, 8, 18, 32, 10, 2
Electron Configuration[Xe] 4f14 5d2 6s2
Valence Electrons5d2 6s2
Valence (Valency)4
Main Oxidation States4
Oxidation States-2, 0, 1, 2, 3, 4
Atomic Term Symbol (Quantum Numbers)3F2

Bohr Atomic Model of Hafnium - Electrons per energy level

72 Hf Hafnium - Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Hafnium - neutral Hafnium atom

Abbreviated electronic configuration of Hafnium

The ground state abbreviated electronic configuration of Neutral Hafnium atom is [Xe] 4f14 5d2 6s2. The portion of Hafnium 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 5d2 6s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Hafnium

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

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d2 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 Hafnium
    Atomic Structure of Hafnium

    Hafnium atomic radius is 208 pm, while it's covalent radius is 150 pm.

    Atomic Radius Calculated

    208 pm (2.08 Å)

    Atomic Radius Empirical

    155 pm (1.55 Å)

    Atomic Volume13.44 cm3/mol
    Covalent Radius150 pm (1.5 Å)
    Van der Waals Radius-
    Neutron Cross Section104
    Neutron Mass Absorption 0.02

    Atomic Spectrum of Hafnium

    Atomic Spectrum of Hafnium | SchoolMyKids

    Hafnium Chemical Properties: Hafnium Ionization Energies and electron affinity

    The electron affinity of Hafnium is 0 kJ/mol.

    Valence4
    Electronegativity1.3
    ElectronAffinity0 kJ/mol

    Ionization Energy of Hafnium

    Refer to table below for Ionization energies of Hafnium

    Ionization energy numberEnthalpy - kJ/mol
    1st658.5
    2nd1440
    3rd2250
    4th3216

    Hafnium Physical Properties

    Refer to below table for Hafnium Physical Properties

    Density13.31 g/cm3(when liquid at m.p density is $12 g/cm3)
    Molar Volume13.44 cm3/mol

    Elastic Properties

    Young Modulus78
    Shear Modulus30 GPa
    Bulk Modulus 110 GPa
    Poisson Ratio0.37

    Hardness of Hafnium - Tests to Measure of Hardness of Element

    Mohs Hardness5.5 MPa
    Vickers Hardness1760 MPa
    Brinell Hardness1700 MPa

    Hafnium Electrical Properties

    Hafnium is Conductor of electricity. Refer to table below for the Electrical properties ofHafnium

    Electrical Conductivity3300000 S/m
    Resistivity3e-7 m Ω
    Superconducting Point0.128

    Hafnium Heat and Conduction Properties

    Thermal Conductivity23 W/(m K)
    Thermal Expansion0.0000059 /K

    Hafnium Magnetic Properties

    Magnetic TypeParamagnetic
    Curie Point-
    Mass Magnetic Susceptibility5.3e-9 m3/kg
    Molar Magnetic Susceptibility9.46e-10 m3/mol
    Volume Magnetic Susceptibility0.0000705

    Optical Properties of Hafnium

    Refractive Index-

    Acoustic Properties of Hafnium

    Speed of Sound3010 m/s

    Hafnium Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Hafnium

    Melting Point2506 K (2232.85°C, 4051.1299999999997 °F)
    Boiling Point4876 K (4602.85°C, 8317.130000000001 °F)
    Critical Temperature-
    Superconducting Point0.128

    Enthalpies of Hafnium

    Heat of Fusion25.5 kJ/mol
    Heat of Vaporization630 kJ/mol
    Heat of Combustion-

    Hafnium Isotopes - Nuclear Properties of Hafnium

    Hafnium has 36 isotopes, with between 153 and 188 nucleons. Hafnium has 5 stable naturally occuring isotopes.

    Isotopes of Hafnium - Naturally occurring stable Isotopes: 176Hf, 177Hf, 178Hf, 179Hf, 180Hf.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    153Hf7281153Synthetic
    154Hf7282154Synthetic
    155Hf7283155Synthetic
    156Hf7284156Synthetic
    157Hf7285157Synthetic
    158Hf7286158Synthetic
    159Hf7287159Synthetic
    160Hf7288160Synthetic
    161Hf7289161Synthetic
    162Hf7290162Synthetic
    163Hf7291163Synthetic
    164Hf7292164Synthetic
    165Hf7293165Synthetic
    166Hf7294166Synthetic
    167Hf7295167Synthetic
    168Hf7296168Synthetic
    169Hf7297169Synthetic
    170Hf7298170Synthetic
    171Hf7299171Synthetic
    172Hf72100172Synthetic
    173Hf72101173Synthetic
    174Hf721021740.16%StableN/A
    175Hf72103175Synthetic
    176Hf721041765.26%StableN/A
    177Hf7210517718.6%StableN/A
    178Hf7210617827.28%Stable
    179Hf7210717913.62%StableN/A
    180Hf7210818035.08%StableN/A
    181Hf72109181Synthetic
    182Hf72110182Synthetic
    183Hf72111183Synthetic
    184Hf72112184Synthetic
    185Hf72113185Synthetic
    186Hf72114186Synthetic
    187Hf72115187Synthetic
    188Hf72116188Synthetic

    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)CAS7440-58-6
    RTECS NumberRTECSMG4600000
    CID Number CID23986
    Gmelin Number-
    NSC Number-

    Compare Hafnium with other elements

    Compare Hafnium with all Group 4 elements

    Compare Hafnium with all Period 6 elements

    Compare Hafnium with all Transition Metal elements