Tc - Technetium

43
Tc
Technetium

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

Element 43 of Periodic table is Technetium with atomic number 43, atomic weight 98. Technetium, symbol Tc, has a Simple Hexagonal structure and Silver color. Technetium is a Transition Metal element. It is part of group 7 (manganese family). Know everything about Technetium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.

Technetium (/tɛkˈniːʃiəm/) is a chemical element with symbol Tc and atomic number 43. It is the element with the lowest atomic number in the periodic table that has no stable isotopes:every form of it is radioactive. Nearly all technetium is produced synthetically, and only minute amounts are found in nature.

It belongs to group 7 of the periodic table having trivial name null. You can also download Printable Periodic Table of Elements Flashcards for Technetium in a PDF format.

Technetium Facts

Read key information and facts about element Technetium

NameTechnetium
Atomic Number43
Atomic SymbolTc
Atomic Weight98
PhaseSolid
ColorSilver
Appearanceshiny gray metal
ClassificationTransition Metal
Natural OccuranceFrom decay
Group in Periodic Table7
Group Namemanganese family
Period in Periodic Tableperiod 5
Block in Periodic Tabled-block
Electronic Configuration[Kr] 4d5 5s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 13, 2
Melting Point2430 K
Boiling Point4538 K
CAS NumberCAS7440-26-8
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 Technetium 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 43 to find Technetium 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 Technetium on periodic table look for cross section of group 7 and period 5 in the modern periodic table.

Technetium History

The element Technetium was discovered by C. Perrier and E. Segrè in year 1937 in Italy. Technetium was first isolated by C. Perrier & E.Segrè in 1937. Technetium derived its name from the Greek tekhnètos meaning 'artificial'.

Discovered By C. Perrier and E. Segrè
Discovery Date 1937 in Italy
First Isolation 1937
Isolated by C. Perrier & E.Segrè

The two discovered a new element in a molybdenum sample that was used in acyclotron, the firstsynthetic elementto be discovered, though it was later found out that it does occur naturally in minuscule trace quantities. It had been predicted by Mendeleev in 1871 as eka-manganese.

Technetium Uses

Technetium is a synthesized element that can be used as a radioactive tracer.

Technetium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Technetium 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 Universe--
Abundance in Sun--
Abundance in Meteorites--
Abundance in Earth's Crust--
Abundance in Oceans--
Abundance in Humans--

Crystal Structure of Technetium

The solid state structure of Technetium 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
273.5 pm273.5 pm438.8 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
43 Tc Technetium - 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.

Technetium Atomic and Orbital Properties

Technetium atoms have 43 electrons and the electronic shell structure is [2, 8, 18, 13, 2] with Atomic Term Symbol (Quantum Numbers) 6S5/2.

Atomic Number43
Number of Electrons (with no charge)43
Number of Protons43
Mass Number98
Number of Neutrons55
Shell structure (Electrons per energy level)2, 8, 18, 13, 2
Electron Configuration[Kr] 4d5 5s2
Valence Electrons4d5 5s2
Valence (Valency)6
Main Oxidation States4, 7
Oxidation States-3, -1, 0, 1, 2, 3, 4, 5, 6, 7
Atomic Term Symbol (Quantum Numbers)6S5/2

Bohr Atomic Model of Technetium - Electrons per energy level

43 Tc Technetium Electron Shell Structure | SchoolMyKids
nspdf

Ground State Electronic Configuration of Technetium - neutral Technetium atom

Abbreviated electronic configuration of Technetium

The ground state abbreviated electronic configuration of Neutral Technetium atom is [Kr] 4d5 5s2. The portion of Technetium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Kr]. 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 4d5 5s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Technetium

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

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s2

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 Technetium

Atomic Structure of Technetium

Technetium atomic radius is 183 pm, while it's covalent radius is 156 pm.

Atomic Radius Calculated183 pm(1.83 Å)
Atomic Radius Empirical135 pm (1.35 Å)
Atomic Volume8.522 cm3/mol
Covalent Radius156 pm (1.56 Å)
Van der Waals Radius-
Neutron Cross Section22
Neutron Mass Absorption -

Spectral Lines of Technetium - Atomic Spectrum of Technetium

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 Technetium

Emission Spectrum of Technetium | SchoolMyKids

Absorption spectrum of Technetium

Absorption Spectrum of Technetium | SchoolMyKids

Technetium Chemical Properties: Technetium Ionization Energies and electron affinity

The electron affinity of Technetium is 53 kJ/mol.

Valence6
Electronegativity1.9
ElectronAffinity53 kJ/mol

Ionization Energy of Technetium

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 Technetium

Ionization energy numberEnthalpy - kJ/mol
1st702
2nd1470
3rd2850

Technetium Physical Properties

Refer to below table for Technetium Physical Properties

Density11.5 g/cm3
Molar Volume8.522 cm3/mol

Elastic Properties

Young Modulus-
Shear Modulus-
Bulk Modulus -
Poisson Ratio-

Hardness of Technetium - Tests to Measure of Hardness of Element

Mohs Hardness-
Vickers Hardness-
Brinell Hardness-

Technetium 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).

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

Electrical conductors Conductor
Electrical Conductivity5000000 S/m
Resistivity2e-7 m Ω
Superconducting Point7.8

Technetium Heat and Conduction Properties

Thermal Conductivity51 W/(m K)
Thermal Expansion-

Technetium Magnetic Properties

Magnetic TypeParamagnetic
Curie Point-
Mass Magnetic Susceptibility3.42e-8 m3/kg
Molar Magnetic Susceptibility3.352e-9 m3/mol
Volume Magnetic Susceptibility0.0003933

Optical Properties of Technetium

Refractive Index-

Acoustic Properties of Technetium

Speed of Sound-

Technetium Thermal Properties - Enthalpies and thermodynamics

Refer to table below for Thermal properties of Technetium

Melting Point2430 K(2156.85 °C, 3914.330 °F)
Boiling Point4538 K(4264.85 °C, 7708.730 °F)
Critical Temperature-
Superconducting Point7.8

Enthalpies of Technetium

Heat of Fusion23 kJ/mol
Heat of Vaporization550 kJ/mol
Heat of Combustion-

Technetium Isotopes - Nuclear Properties of Technetium

Technetium has 34 isotopes, with between 85 and 118 nucleons. Technetium has 1 stable naturally occuring isotopes.

Isotopes of Technetium - Naturally occurring stable Isotopes: None.

IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
85Tc434285Synthetic
86Tc434386Synthetic
87Tc434487Synthetic
88Tc434588Synthetic
89Tc434689Synthetic
90Tc434790Synthetic
91Tc434891Synthetic
92Tc434992Synthetic
93Tc435093Synthetic
94Tc435194Synthetic
95Tc435295Synthetic
96Tc435396Synthetic
97Tc435497Synthetic
98Tc435598Synthetic4.12×10^6 yearsBetaDecay
99Tc435699Synthetic
100Tc4357100Synthetic
101Tc4358101Synthetic
102Tc4359102Synthetic
103Tc4360103Synthetic
104Tc4361104Synthetic
105Tc4362105Synthetic
106Tc4363106Synthetic
107Tc4364107Synthetic
108Tc4365108Synthetic
109Tc4366109Synthetic
110Tc4367110Synthetic
111Tc4368111Synthetic
112Tc4369112Synthetic
113Tc4370113Synthetic
114Tc4371114Synthetic
115Tc4372115Synthetic
116Tc4373116Synthetic
117Tc4374117Synthetic
118Tc4375118Synthetic

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.

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)CAS7440-26-8
RTECS Number-
CID Number -
Gmelin Number-
NSC Number-

Compare Technetium with other elements

Compare Technetium with Group 7, Period 5 and Transition Metal elements of the periodic table.

Compare Technetium with all Group 7 elements

Compare Technetium with all Period 5 elements

Compare Technetium with all Transition Metal elements

Frequently Asked Questions (FAQ)

Find the answers to the most frequently asked questions about Technetium

The electronic configuration of Technetium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s2.

The abbreviated electronic configuration of Technetium is [Kr] 4d5 5s2. 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 Technetium is Tc. Technetium is a chemical element with symbol Tc and atomic number 43.

Technetium is a chemical element with the symbol Tc and atomic number 43. Technetium is the 43 element on the periodic table. It is located in group 7 and period 5 in the modern periodic table.

The atomic number of Technetium is 43.

Technetium is of Silver color.

The element Technetium was discovered by C. Perrier and E. Segrè in year 1937 in Italy. Technetium was first isolated by C. Perrier & E.Segrè in 1937.

Technetium has 6 valence electrons. Technetium has 43 electrons out of which 6 valence electrons are present in the 4d5 5s2 outer orbitals of atom.

Melting Point of Technetium is 2430 K.

Boiling Point of Technetium is 4538 K.

Melting Point of Technetium in Kelvin is 2430 K.

Boiling Point of Technetium in Kelvin is 4538 K.

Melting Point of Technetium in Celsius is 2156.85 °C.

Boiling Point of Technetium in Celsius is 4264.85 °C.

Melting Point of Technetium in Fahrenheit is 3914.33 °F.

Boiling Point of Technetium in Fahrenheit is 7708.73 °F.

The electronic configuration of Technetium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s2.

The electronic configuration of Technetium will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s2.