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Tm Thulium
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

69
Tm
Thulium
Element 69 of Periodic table is Thulium with atomic number 69, atomic weight 168.93421. Thulium, symbol Tm, has a Simple Hexagonal structure and Silver color. Thulium is a Lanthanide element. It is part of group null (). Know everything about Thulium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
69 Tm - Thulium | SchoolMyKids

Thulium is a chemical element with symbol Tm and atomic number 69. It is the thirteenth and antepenultimate (third-last) element in the Lanthanide series. Like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds.

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

Thulium Facts

Read key information and facts about element Thulium

NameThulium
Atomic Number69
Atomic SymbolTm
Atomic Weight168.93421
PhaseSolid
ColorSilver
Appearancesilvery gray
ClassificationLanthanide
Natural OccurancePrimordial
Group in Periodic Table-
Group Name
Period in Periodic Tableperiod 6
Block in Periodic Tablef-block
Electronic Configuration[Xe] 4f13 6s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 31, 8, 2
Melting Point1818 K
Boiling Point2223 K
CAS NumberCAS7440-30-4
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
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 Thulium 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 69 to find Thulium 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 Thulium on periodic table look for cross section of group - and period 6 in the modern periodic table.

Thulium History

The element Thulium was discovered by T. Cleve in year 1879 in Sweden. Thulium was first isolated by T. Cleve in 1879. Thulium derived its name from Thule, the ancient name for Scandinavia.

Discovered By T. Cleve
Discovery Date 1879 in Sweden
First Isolation 1879
Isolated by T. Cleve

Cleve split Marignac's erbia into erbia proper and two new elements, thulium and holmium.

Thulium Uses

Thulium is the least naturally-occurring element on earth. When irradiated, thulium produces an isotope that emits x-rays and can be used to make a lightweight, portable x-ray machine. Thulium is also used in some surgical lasers

Thulium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Thulium 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 Universe0.10.001
Abundance in Sun0.20.001
Abundance in Meteorites303
Abundance in Earth's Crust45050
Abundance in Oceans0.00020.000007
Abundance in Humans--

Crystal Structure of Thulium

The solid state structure of Thulium 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
353.75 pm353.75 pm555.46 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
69 Tm Thulium - 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.

Thulium Atomic and Orbital Properties

Thulium atoms have 69 electrons and the electronic shell structure is [2, 8, 18, 31, 8, 2] with Atomic Term Symbol (Quantum Numbers) 2F7/2.

Atomic Number69
Number of Electrons (with no charge)69
Number of Protons69
Mass Number169
Number of Neutrons100
Shell structure (Electrons per energy level)2, 8, 18, 31, 8, 2
Electron Configuration[Xe] 4f13 6s2
Valence Electrons4f13 6s2
Valence (Valency)3
Main Oxidation States3
Oxidation States0, 1, 2, 3
Atomic Term Symbol (Quantum Numbers)2F7/2

Bohr Atomic Model of Thulium - Electrons per energy level

69 Tm Thulium Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Thulium - neutral Thulium atom

Abbreviated electronic configuration of Thulium

The ground state abbreviated electronic configuration of Neutral Thulium atom is [Xe] 4f13 6s2. The portion of Thulium 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 4f13 6s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Thulium

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

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f13 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 Thulium
    Atomic Structure of Thulium

    Thulium atomic radius is 222 pm, while it's covalent radius is -.

    Atomic Radius Calculated

    222 pm(2.22 Å)

    Atomic Radius Empirical

    175 pm (1.75 Å)

    Atomic Volume19.13 cm3/mol
    Covalent Radius-
    Van der Waals Radius-
    Neutron Cross Section105
    Neutron Mass Absorption 0.025

    Spectral Lines of Thulium - Atomic Spectrum of Thulium

    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 Thulium

    Emission Spectrum of Thulium | SchoolMyKids

    Absorption spectrum of Thulium

    Absorption Spectrum of Thulium | SchoolMyKids

    Thulium Chemical Properties: Thulium Ionization Energies and electron affinity

    The electron affinity of Thulium is 50 kJ/mol.

    Valence3
    Electronegativity1.25
    ElectronAffinity50 kJ/mol

    Ionization Energy of Thulium

    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 Thulium

    Ionization energy numberEnthalpy - kJ/mol
    1st596.7
    2nd1160
    3rd2285
    4th4120

    Thulium Physical Properties

    Refer to below table for Thulium Physical Properties

    Density9.321 g/cm3(when liquid at m.p density is $8.56 g/cm3)
    Molar Volume19.13 cm3/mol

    Elastic Properties

    Young Modulus74
    Shear Modulus31 GPa
    Bulk Modulus 45 GPa
    Poisson Ratio0.21

    Hardness of Thulium - Tests to Measure of Hardness of Element

    Mohs Hardness-
    Vickers Hardness520 MPa
    Brinell Hardness471 MPa

    Thulium 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).

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

    Electrical conductors Conductor
    Electrical Conductivity1400000 S/m
    Resistivity7e-7 m Ω
    Superconducting Point-

    Thulium Heat and Conduction Properties

    Thermal Conductivity17 W/(m K)
    Thermal Expansion0.0000133 /K

    Thulium Magnetic Properties

    Magnetic TypeParamagnetic
    Curie Point25 K
    Mass Magnetic Susceptibility0.00000199 m3/kg
    Molar Magnetic Susceptibility3.36179e-7 m3/mol
    Volume Magnetic Susceptibility0.0185488

    Optical Properties of Thulium

    Refractive Index-

    Acoustic Properties of Thulium

    Speed of Sound-

    Thulium Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Thulium

    Melting Point1818 K(1544.85 °C, 2812.730 °F)
    Boiling Point2223 K(1949.85 °C, 3541.730 °F)
    Critical Temperature-
    Superconducting Point-

    Enthalpies of Thulium

    Heat of Fusion16.8 kJ/mol
    Heat of Vaporization250 kJ/mol
    Heat of Combustion-

    Thulium Isotopes - Nuclear Properties of Thulium

    Thulium has 35 isotopes, with between 145 and 179 nucleons. Thulium has 1 stable naturally occuring isotopes.

    Isotopes of Thulium - Naturally occurring stable Isotopes: 169Tm.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    145Tm6976145Synthetic
    146Tm6977146Synthetic
    147Tm6978147Synthetic
    148Tm6979148Synthetic
    149Tm6980149Synthetic
    150Tm6981150Synthetic
    151Tm6982151Synthetic
    152Tm6983152Synthetic
    153Tm6984153Synthetic
    154Tm6985154Synthetic
    155Tm6986155Synthetic
    156Tm6987156Synthetic
    157Tm6988157Synthetic
    158Tm6989158Synthetic
    159Tm6990159Synthetic
    160Tm6991160Synthetic
    161Tm6992161Synthetic
    162Tm6993162Synthetic
    163Tm6994163Synthetic
    164Tm6995164Synthetic
    165Tm6996165Synthetic
    166Tm6997166Synthetic
    167Tm6998167Synthetic
    168Tm6999168Synthetic
    169Tm69100169100%Stable
    170Tm69101170Synthetic
    171Tm69102171Synthetic
    172Tm69103172Synthetic
    173Tm69104173Synthetic
    174Tm69105174Synthetic
    175Tm69106175Synthetic
    176Tm69107176Synthetic
    177Tm69108177Synthetic
    178Tm69109178Synthetic
    179Tm69110179Synthetic

    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.

    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)CAS7440-30-4
    RTECS Number-
    CID Number CID23961
    Gmelin Number-
    NSC Number-

    Compare Thulium with other elements

    Compare Thulium with all Group elements

    Compare Thulium with all Period 6 elements

    Compare Thulium with all Lanthanide elements

    FAQs

    What is the electronic configuration of Thulium?

    The electronic configuration of Thulium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f13 6s2.

    What is the abbreviated electronic configuration of Thulium?

    The abbreviated electronic configuration of Thulium is [Xe] 4f13 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.

    What is the symbol of Thulium?

    Symbol of Thulium is Tm. Thulium is a chemical element with symbol Tm and atomic number 69.

    What is the position of Thulium in the Periodic Table?

    Thulium is a chemical element with the symbol Tm and atomic number 69. Thulium is the 69 element on the periodic table. It is located in group null and period 6 in the modern periodic table.

    What is the atomic number of Thulium?

    The atomic number of Thulium is 69.

    What is the color of Thulium?

    Thulium is of Silver color.

    Who discovered Thulium?

    The element Thulium was discovered by T. Cleve in year 1879 in Sweden. Thulium was first isolated by T. Cleve in 1879.

    How many valence electrons does a Thulium atom have?

    Thulium has 3 valence electrons. Thulium has 69 electrons out of which 3 valence electrons are present in the 4f13 6s2 outer orbitals of atom.

    What is the melting Point of Thulium?

    Melting Point of Thulium is 1818 K.

    What is the boiling Point of Thulium?

    Boiling Point of Thulium is 2223 K.

    What is the melting Point of Thulium in Kelvin?

    Melting Point of Thulium in Kelvin is 1818 K.

    What is the boiling Point of Thulium in Kelvin?

    Boiling Point of Thulium in Kelvin is 2223 K.

    What is the melting Point of Thulium in Celsius?

    Melting Point of Thulium in Celsius is 1544.85 °C.

    What is the boiling Point of Thulium in Celsius?

    Boiling Point of Thulium in Celsius is 1949.85 °C.

    What is the melting Point of Thulium in Fahrenheit?

    Melting Point of Thulium in Fahrenheit is 2812.73 °F.

    What is the boiling Point of Thulium in Fahrenheit?

    Boiling Point of Thulium in Fahrenheit is 3541.73 °F.

    What is the electronic configuration of Thulium 69?

    The electronic configuration of Thulium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f13 6s2.

    How do you write the electron configuration for Thulium?

    The electronic configuration of Thulium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f13 6s2.