Molybdenum contributes strength and wear resistance to steel alloys, while molybdenum disulfide serves as a lubricant. The element also occurs in enzymes, including some nitrogen-fixing systems. Its different chemical settings connect engine components, sliding surfaces, and the biological conversion of atmospheric nitrogen.
FROM ELEMENT TO APPLICATION
AN ELEMENT IN CONTEXT
Why is molybdenum content only part of an alloy performance explanation?
Molybdenum-containing steel or superalloy
FOLLOW THIS RELATIONSHIP
Choose the material combination
Molybdenum is incorporated into steels or superalloys alongside other elements. The selected combination addresses demands such as strength, wear or corrosion.
Explore the model (optional)
MoFORM → INTERACTION → CONSEQUENCE
Follow the explanation in either direction. These are authored steps, not a physical clock.
Optional: check your understanding
USE THE EXPLANATION
Which comparison best tests whether two molybdenum-containing alloys resist the same service environment?
Molybdenite looked enough like graphite and lead-bearing to invite confusion. In 1778, Carl Wilhelm Scheele showed through chemical investigation that it contained something different. Peter Jacob Hjelm prepared molybdenum metal in 1781. The story is a useful reminder that similar appearance is weak evidence of identical composition: the decisive change came from comparing chemical products, not simply choosing a better mineral name.
1778
Distinct chemistry recognized
Scheele distinguished molybdenite from graphite and lead minerals.
Molybdenite, molybdenum disulfide, is an important molybdenum mineral. Recovery may accompany mining of other metals, including copper. The sulfur-bearing mineral, an intermediate, and metal occupy different stages of production. That distinction explains why a deposit can support several materials rather than one isolated element.
Molybdenum is a refractory metal, useful where materials must tolerate demanding temperatures and mechanical conditions. Its compounds can behave quite differently: molybdenum disulfide serves as a lubricant. Comparing these forms prevents a common shortcut in element stories: a property of one compound cannot automatically be assigned to the pure metal.
Each section links its supporting references. Descriptions and diagrams were authored for this atlas. Source checks completed. Source checks dated 2026-09-06.
CITE THIS PAGE
Family labels and the group-3 layout are teaching conventions. A table position does not establish an unknown bulk property. Electronic configurations refer to neutral atoms; ions and material environments require their own account.
Read each reference property together with its units, conditions and the reference information below.
Not yet recorded: electron affinity, second ionization energy, ground-state term symbol, van der waals radius, thermal conductivity, specific heat capacity, electrical resistivity, crystal structure, lattice parameter a, space group, abundance in seawater, abundance in the universe, annual production, supply-risk listing, hazard classification, biological role, cas registry number, pubchem cid, wikidata item. These families are declared and awaiting an ingestion run against the source each names; they are listed here rather than shown as empty rows.
Physical
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Phase at 20 °C
solid
293.15 K, 101.325 kPa
Melting point in K
2896 K
at standard pressure unless noted
Boiling point in K
4912 K
101.325 kPa
Density in g/cm³
10.28 g/cm³
solids and liquids at 293 K; gases at 273 K and 101.325 kPa
Atomic and electronic
Intended reference: Pauling electronegativity scale · Widely tabulated; original in The Nature of the Chemical Bond
Electronegativity in Pauling
2.16 Pauling
Pauling scale
First ionization energy in kJ/mol
684.3 kJ/mol
gas-phase neutral atom, ground state
Covalent radius in pm
154 pm
single-bond covalent radius
Common oxidation states
+4, +6
states met in ordinary compounds; not exhaustive
Occurrence and identity
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Abundance in the crust in mg/kg
1.2 mg/kg
upper continental crust, mass fraction
Has stable isotopes
Yesderived
Discovery year in CE
1778 CEderived
WHERE IT SITS AMONG ITS NEIGHBORS
Electronegativity across period 5
Mo 2.16 Pauling · Molybdenum
Electronegativity across period 5. Exact values.
Rb
0.82
Sr
0.95
Y
1.22
Zr
1.33
Nb
1.6
Mo
2.16
Tc
1.9
Ru
2.2
Rh
2.28
Pd
2.2
Ag
1.93
Cd
1.69
In
1.78
Sn
1.96
Sb
2.05
Te
2.1
I
2.66
Xe
2.6
Electronegativity down group 6
Mo 2.16 Pauling · Molybdenum
Electronegativity down group 6. Exact values.
Cr
1.66
Mo
2.16
W
2.36
The trend uses the same reference-property values as the periodic table. Elements with no recorded value are left out of the line rather than drawn at zero.
