Mo Molybdenum
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
Molybdenum is a chemical element with symbol Mo and atomic number 42. The name is from Neo-Latin molybdaenum, from Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele.
It belongs to group 6 of the periodic table having trivial name .
Molybdenum Facts
Read key information and facts about element Molybdenum
| Name | Molybdenum |
| Atomic Number | 42 |
| Atomic Symbol | Mo |
| Atomic Weight | 95.94 |
| Phase | Solid |
| Color | Gray |
| Appearance | gray metallic |
| Classification | Transition Metal |
| Group in Periodic Table | 6 |
| Group Name | chromium family |
| Period in Periodic Table | period 5 |
| Block in Periodic Table | d -block |
| Electronic Configuration | [Kr] 4d5 5s1 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 13, 1 |
| Melting Point | 2896 K |
| Boiling Point | 4912 K |
| CAS Number | CAS7439-98-7 |
How to Locate Molybdenum 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 42 to find Molybdenum 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 Molybdenum on periodic table look for cross section of group 6 and period 5 in the modern periodic table.
Molybdenum History
The element Molybdenum was discovered by W. Scheele in year 1778 in Sweden. Molybdenum was first isolated by J. Hjelm in 1781. Molybdenum derived its name from the Greek word molybdos meaning 'lead'.
Scheele recognised the metal as a constituent ofmolybdena.
Molybdenum Presence: Abundance in Nature and Around Us
The table below shows the abundance of Molybdenum 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 | 5 | 0.1 |
| Abundance in Sun | 9 | 0.1 |
| Abundance in Meteorites | 1200 | 250 |
| Abundance in Earth's Crust | 1100 | 230 |
| Abundance in Oceans | 10 | 0.64 |
| Abundance in Humans | 100 | 7 |
Crystal Structure of Molybdenum
The solid state structure of Molybdenum is Body Centered Cubic.
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)
| a | b | c |
|---|---|---|
| 314.7 pm | 314.7 pm | 314.7 pm |
and the angles between them Lattice Angles (alpha, beta and gamma).
| alpha | beta | gamma |
|---|---|---|
| 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 Name | Im_ 3m |
| Space Group Number | 229 |
| Crystal Structure | Body Centered Cubic |
| Number of atoms per unit cell | 2 |
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
Molybdenum Atomic and Orbital Properties
Molybdenum atoms have 42 electrons and the electronic shell structure is [2, 8, 18, 13, 1] with Atomic Term Symbol (Quantum Numbers) 7S3.
| Atomic Number | 42 |
| Number of Electrons (with no charge) | 42 |
| Number of Protons | 42 |
| Mass Number | 96 |
| Number of Neutrons | 54 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 13, 1 |
| Electron Configuration | [Kr] 4d5 5s1 |
| Valence Electrons | 4d5 5s1 |
| Valence (Valency) | 6 |
| Main Oxidation States | 4, 6 |
| Oxidation States | -4, -2, -1, 0, 1, 2, 3, 4, 5, 6 |
| Atomic Term Symbol (Quantum Numbers) | 7S3 |
Bohr Atomic Model of Molybdenum - Electrons per energy level
| n | s | p | d | f |
|---|
Ground State Electronic Configuration of Molybdenum - neutral Molybdenum atom
Abbreviated electronic configuration of Molybdenum
The ground state abbreviated electronic configuration of Neutral Molybdenum atom is [Kr] 4d5 5s1. The portion of Molybdenum 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 5s1, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Molybdenum
Complete ground state electronic configuration for the Molybdenum atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s1
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
Atomic Structure of Molybdenum
Molybdenum atomic radius is 190 pm, while it's covalent radius is 145 pm.
| Atomic Radius Calculated | 190 pm (1.9 Å) |
| Atomic Radius Empirical | 145 pm (1.45 Å) |
| Atomic Volume | 9.333 cm3/mol |
| Covalent Radius | 145 pm (1.45 Å) |
| Van der Waals Radius | - |
| Neutron Cross Section | 2.6 |
| Neutron Mass Absorption | 0.0009 |
Atomic Spectrum of Molybdenum
Molybdenum Chemical Properties: Molybdenum Ionization Energies and electron affinity
The electron affinity of Molybdenum is 71.9 kJ/mol.
| Valence | 6 |
| Electronegativity | 2.16 |
| ElectronAffinity | 71.9 kJ/mol |
Ionization Energy of Molybdenum
Refer to table below for Ionization energies of Molybdenum
| Ionization energy number | Enthalpy - kJ/mol |
|---|---|
| 1st | 684.3 |
| 2nd | 1560 |
| 3rd | 2618 |
| 4th | 4480 |
| 5th | 5257 |
| 6th | 6640.8 |
| 7th | 12125 |
| 8th | 13860 |
| 9th | 15835 |
| 10th | 17980 |
| 11th | 20190 |
| 12th | 22219 |
| 13th | 26930 |
| 14th | 29196 |
| 15th | 52490 |
| 16th | 55000 |
| 17th | 61400 |
| 18th | 67700 |
| 19th | 74000 |
| 20th | 80400 |
| 21st | 87000 |
| 22nd | 93400 |
| 23rd | 98420 |
| 24th | 104400 |
| 25th | 121900 |
| 26th | 127700 |
| 27th | 133800 |
| 28th | 139800 |
| 29th | 148100 |
| 30th | 154500 |
Molybdenum Physical Properties
Refer to below table for Molybdenum Physical Properties
| Density | 10.28 g/cm3(when liquid at m.p density is $9.33 g/cm3) |
| Molar Volume | 9.333 cm3/mol |
Elastic Properties
| Young Modulus | 329 |
| Shear Modulus | 20 GPa |
| Bulk Modulus | 230 GPa |
| Poisson Ratio | 0.31 |
Hardness of Molybdenum - Tests to Measure of Hardness of Element
| Mohs Hardness | 5.5 MPa |
| Vickers Hardness | 1530 MPa |
| Brinell Hardness | 1500 MPa |
Molybdenum Electrical Properties
Molybdenum is Conductor of electricity. Refer to table below for the Electrical properties ofMolybdenum
| Electrical Conductivity | 20000000 S/m |
| Resistivity | 5e-8 m Ω |
| Superconducting Point | 0.915 |
Molybdenum Heat and Conduction Properties
| Thermal Conductivity | 139 W/(m K) |
| Thermal Expansion | 0.0000048 /K |
Molybdenum Magnetic Properties
| Magnetic Type | Paramagnetic |
| Curie Point | - |
| Mass Magnetic Susceptibility | 1.17e-8 m3/kg |
| Molar Magnetic Susceptibility | 1.122e-9 m3/mol |
| Volume Magnetic Susceptibility | 0.0001203 |
Optical Properties of Molybdenum
| Refractive Index | - |
Acoustic Properties of Molybdenum
| Speed of Sound | 6190 m/s |
Molybdenum Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Molybdenum
| Melting Point | 2896 K (2622.85°C, 4753.129999999999 °F) |
| Boiling Point | 4912 K (4638.85°C, 8381.93 °F) |
| Critical Temperature | - |
| Superconducting Point | 0.915 |
Enthalpies of Molybdenum
| Heat of Fusion | 36 kJ/mol |
| Heat of Vaporization | 600 kJ/mol |
| Heat of Combustion | - |
Molybdenum Isotopes - Nuclear Properties of Molybdenum
Molybdenum has 33 isotopes, with between 83 and 115 nucleons. Molybdenum has 6 stable naturally occuring isotopes.
Isotopes of Molybdenum - Naturally occurring stable Isotopes: 92Mo, 94Mo, 95Mo, 96Mo, 97Mo, 98Mo.
| Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
|---|---|---|---|---|---|---|
| 83Mo | 42 | 41 | 83 | Synthetic | ||
| 84Mo | 42 | 42 | 84 | Synthetic | ||
| 85Mo | 42 | 43 | 85 | Synthetic | ||
| 86Mo | 42 | 44 | 86 | Synthetic | ||
| 87Mo | 42 | 45 | 87 | Synthetic | ||
| 88Mo | 42 | 46 | 88 | Synthetic | ||
| 89Mo | 42 | 47 | 89 | Synthetic | ||
| 90Mo | 42 | 48 | 90 | Synthetic | ||
| 91Mo | 42 | 49 | 91 | Synthetic | ||
| 92Mo | 42 | 50 | 92 | 14.84% | Stable | N/A |
| 93Mo | 42 | 51 | 93 | Synthetic | ||
| 94Mo | 42 | 52 | 94 | 9.25% | Stable | N/A |
| 95Mo | 42 | 53 | 95 | 15.92% | Stable | N/A |
| 96Mo | 42 | 54 | 96 | 16.68% | Stable | |
| 97Mo | 42 | 55 | 97 | 9.55% | Stable | N/A |
| 98Mo | 42 | 56 | 98 | 24.13% | Stable | N/A |
| 99Mo | 42 | 57 | 99 | Synthetic | ||
| 100Mo | 42 | 58 | 100 | 9.63% | Stable | N/A |
| 101Mo | 42 | 59 | 101 | Synthetic | ||
| 102Mo | 42 | 60 | 102 | Synthetic | ||
| 103Mo | 42 | 61 | 103 | Synthetic | ||
| 104Mo | 42 | 62 | 104 | Synthetic | ||
| 105Mo | 42 | 63 | 105 | Synthetic | ||
| 106Mo | 42 | 64 | 106 | Synthetic | ||
| 107Mo | 42 | 65 | 107 | Synthetic | ||
| 108Mo | 42 | 66 | 108 | Synthetic | ||
| 109Mo | 42 | 67 | 109 | Synthetic | ||
| 110Mo | 42 | 68 | 110 | Synthetic | ||
| 111Mo | 42 | 69 | 111 | Synthetic | ||
| 112Mo | 42 | 70 | 112 | Synthetic | ||
| 113Mo | 42 | 71 | 113 | Synthetic | ||
| 114Mo | 42 | 72 | 114 | Synthetic | ||
| 115Mo | 42 | 73 | 115 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
Database Search
List of unique identifiers to search the element in various chemical registry databases
| Database | Identifier number |
|---|---|
| CAS Number - Chemical Abstracts Service (CAS) | CAS7439-98-7 |
| RTECS Number | RTECSQA4680000 |
| CID Number | CID23932 |
| Gmelin Number | - |
| NSC Number | - |
Compare Molybdenum with other elements
Compare Molybdenum with all Group 6 elements
Compare Molybdenum with all Period 5 elements
Compare Molybdenum with all Transition Metal elements
FAQs
What is the electronic configuration of Molybdenum?
The electronic configuration of Molybdenum is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s1.
What is the abbreviated electronic configuration of Molybdenum?
The abbreviated electronic configuration of Molybdenum is [Kr] 4d5 5s1. 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 Molybdenum?
Symbol of Molybdenum is Mo. Molybdenum is a chemical element with symbol Mo and atomic number 42.
What is the position of Molybdenum in the Periodic Table?
Molybdenum is a chemical element with the symbol Mo and atomic number 42. Molybdenum is the 42 element on the periodic table. It is located in group 6 and period 5 in the modern periodic table.
What is the atomic number of Molybdenum?
The atomic number of Molybdenum is 42.
What is the color of Molybdenum?
Molybdenum is of Gray color.
Who discovered Molybdenum?
The element Molybdenum was discovered by W. Scheele in year 1778 in Sweden. Molybdenum was first isolated by J. Hjelm in 1781.
How many valence electrons does a Molybdenum atom have?
Molybdenum has 6 valence electrons. Molybdenum has 42 electrons out of which 6 valence electrons are present in the 4d5 5s1 outer orbitals of atom.
What is the melting Point of Molybdenum?
Melting Point of Molybdenum is 2896 K.
What is the boiling Point of Molybdenum?
Boiling Point of Molybdenum is 4912 K.
What is the melting Point of Molybdenum in Kelvin?
Melting Point of Molybdenum in Kelvin is 2896 K.
What is the boiling Point of Molybdenum in Kelvin?
Boiling Point of Molybdenum in Kelvin is 4912 K.
What is the electronic configuration of Molybdenum 42?
The electronic configuration of Molybdenum will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s1.
How do you write the electron configuration for Molybdenum?
The electronic configuration of Molybdenum will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s1.