Atomic / phase data
Reference values are evaluated.
BCC metal
Ordinary molybdenum metal is BCC.
Mo vs MoS₂
Metal, layered compound and biological cofactor contexts are explicitly separated.
Commodity geography
Selected production points are dated examples.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Molybdenum (Mo)
Molybdenum is element 42, a refractory Group 6 metal with a high melting point and rich oxidation chemistry. It strengthens high-temperature alloys, forms layered MoS₂ lubricants and appears in biological molybdenum cofactors.
Molybdenum atomic number, mass, electron configuration and key properties
Molybdenum: quick answers
How many protons, neutrons and electrons does molybdenum have?
Molybdenum’s atomic number is 42, so every molybdenum atom has 42 protons, and a neutral atom also has 42 electrons. Its most common natural isotope, molybdenum-98, has 56 neutrons (other isotopes have different neutron counts).
What is the symbol for molybdenum?
The chemical symbol for molybdenum is Mo.
Is molybdenum a solid, liquid or gas at room temperature?
Molybdenum is a solid at room temperature (about 25 °C).
What family (group) is molybdenum in?
Molybdenum is a transition metal, in group 6, period 5 of the periodic table.
What is the electron configuration of molybdenum?
The ground-state electron configuration of molybdenum is [Kr] 4d⁵ 5s¹.
From atomic number to chemistry
Read these as a chain of causes, not as isolated facts. Each step links to the concept hub if you want the underlying idea explained.
42 protons define molybdenum.
The reference ground-state configuration frames atomic and chemical behavior.
Periodic position organizes recurring trends without replacing element-specific evidence.
The teaching nucleus is one isotope, not the relative atomic mass.
Phase claims preserve measured/evaluated/predicted/unknown evidence labels.
Molybdenum in its period and family
Molybdenum is the Period 5 Group 6 transition metal between chromium and tungsten. Its partly filled 4d shell supports multiple oxidation states, strong metallic bonding and diverse compound chemistry.
Molybdenum Visual Lab
Rotate a ⁹⁸Mo nucleus and BCC metal cell, inspect 4d/5s probability models, then compare refractory metal, layered MoS₂ and catalytic/biological molybdenum chemistry.
Every mark points to one exact feature
The numbered markers explain the same information system used throughout Element Lookup. Unknown or predicted fields remain visibly labelled rather than being replaced with guesses.
Molybdenum in one minute
Atomic number 42 means 42 protons.
The reference ground-state configuration is [Kr] 4d⁵ 5s¹.
Molybdenum metal is BCC and melts near 2895 K.
MoS₂ is a layered compound used as a lubricant and 2D-material platform; it is not metallic Mo.
Molybdenum also participates in important enzyme cofactors.
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 13 · 1 electrons
The 4d and 5s probability clouds are isolated-atom teaching models. d labels are explicit representative angular forms; they are not literal metallic-band or MoS₂ electron-density maps.
Pure molybdenum metal is BCC near room temperature. The conventional-cell viewer is separate from layered MoS₂, molybdate compounds and biological molybdenum cofactors.. The viewer is evidence-aware: measured structures are identified as such; unknown bulk structures stay unknown.
Teaching visualization; not a literal finite sample or thermal trajectory.What this model does—and does not—show
The 4d and 5s probability clouds are isolated-atom teaching models. d labels are explicit representative angular forms; they are not literal metallic-band or MoS₂ electron-density maps.
Where do I meet molybdenum?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
High-strength alloys
Molybdenum improves strength, hardenability and high-temperature performance in steels and superalloys.
Refractory Mo metal → layered MoS₂ → catalytic/biological chemistry
The same element participates in very different material and molecular environments, so “molybdenum” must be interpreted by chemical form.
BCC refractory Mo
Strong metallic bonding supports a high melting point and alloy performance.
Chromium, molybdenum and tungsten
Group 6 connects transition-metal chemistry with increasingly refractory heavy metals.
| Config | 3d⁵4s¹ |
|---|---|
| Melt | 2180 K |
| Config | 4d⁵5s¹ |
|---|---|
| Melt | 2895 K |
| Config | 5d⁴6s² |
|---|---|
| Melt | 3687 K |
Molybdenum properties: atomic, physical, thermal and chemical
Categories follow the science of this element rather than a fixed decorative template. Each row carries condition/provenance context and an evidence label; unknown values stay unknown.
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Atomic number | 42 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 95.95 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Kr] 4d⁵ 5s¹ | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group 6 · Period 5 · d-block | Periodic-table placement | Evaluated |
| Electronegativity | 2.16 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ⁹⁸Mo | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Hard silvery refractory metal · solid at 20 °C | Source-reviewed; see Sources below | Evaluated |
| Density | 10.2 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | Molybdenum metal · body-centred cubic | Pure molybdenum metal is BCC near room temperature. The conventional-cell viewer is separate from layered MoS₂, molybdate compounds and biological molybdenum cofactors. | Measured |
| Classification | Transition metal | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | Pure molybdenum metal is BCC near room temperature. The conventional-cell viewer is separate from layered MoS₂, molybdate compounds and biological molybdenum cofactors. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 2895 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 4912 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, molybdenum remains BCC solid to about 2895 K, liquid to about 4912 K, and gaseous above the boiling reference. | Shared phase registry drives the slider, regions and markers. | Evaluated |
| Condition warning | Temperature and pressure define phase behavior; purity/allotropy may matter. | Teaching condition statement | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Ordinary electrical behavior | Metallic conductor | Qualitative bulk behavior; exact resistivity depends on temperature, purity and alloy state. | Measured |
| Conduction model | Collective solid-state electrons | Do not interpret isolated-atom orbital clouds as literal current paths. | Reviewed |
| Surface / compound caveat | Oxides, salts and alloys can behave differently from the pure metal | Material context | Reviewed |
| Engineering values | Condition-dependent | Use condition-specific materials data for engineering calculations. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Common oxidation states | +6, +5, +4, +3, +2 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Element-specific; see chemistry sections | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Molybdenum is the Period 5 Group 6 transition metal between chromium and tungsten. Its partly filled 4d shell supports multiple oxidation states, strong metallic bonding and diverse compound chemistry. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ⁹⁸Mo | Stable natural isotope | Reference teaching nucleus with 42 protons and 56 neutrons. | Evaluated |
| ⁹⁵Mo | Stable natural isotope | One of several stable natural molybdenum isotopes. | Evaluated |
| ¹⁰⁰Mo | Very long-lived double-beta-decay isotope | Important in rare-event nuclear-physics research. | Evaluated |
| Teaching nucleus | ⁹⁸Mo · 42 protons + 56 neutrons | Reference isotope used in the nucleus model | Reviewed |
Is Molybdenum a solid, liquid or gas? State at temperature
At approximately standard pressure, molybdenum remains BCC solid to about 2895 K, liquid to about 4912 K, and gaseous above the boiling reference.
Where on Earth is Molybdenum found or produced?
Who discovered Molybdenum, and when?
Carl Wilhelm Scheele distinguished molybdena from graphite/lead ores.
Peter Jacob Hjelm isolated molybdenum metal.
Molybdenum became strategically important in high-strength steels and high-temperature alloys.
Uses span alloying, catalysis, lubricants, electronics research and biological chemistry.
From molybdenite to molybdenum products: high-level path
Molybdenum is commonly mined from molybdenite-bearing deposits or recovered as a co-product of copper mining.
Concentrates are processed into molybdenum chemical intermediates.
Industrial refining produces molybdenum metal, ferroalloys or compounds under controlled high-temperature/chemical processes; recipes are outside this guide.
Recycling of alloy scrap and catalysts contributes secondary molybdenum supply.
What is molybdenum used for?
Steel & superalloys
Molybdenum improves high-temperature strength, corrosion resistance and hardenability.
Lubricants
MoS₂ serves as a low-friction solid lubricant, especially where oils are unsuitable.
Catalysis
Molybdenum compounds participate in major industrial catalytic processes.
Electronics research
Layered MoS₂ is studied and used in thin-film and semiconductor technologies.
Molybdenum isotopes and natural abundance
⁹⁸Mo
Stable natural isotopeReference teaching nucleus with 42 protons and 56 neutrons.
⁹⁵Mo
Stable natural isotopeOne of several stable natural molybdenum isotopes.
¹⁰⁰Mo
Very long-lived double-beta-decay isotopeImportant in rare-event nuclear-physics research.
Five-question Molybdenum check
What is molybdenum’s atomic number?
What is the ordinary metal structure?
Which compound is a layered lubricant?
What is a major industrial role?
What does the 4d orbital viewer represent?
Molybdenum questions students commonly ask
Each answer starts with the direct fact, then explains the chemistry, evidence or material context so the result is understandable rather than merely memorized.
What is molybdenum?
Short answer: Molybdenum is element 42, a refractory transition metal.
Atomic number 42 means every molybdenum nucleus contains 42 protons. In the periodic table, Molybdenum is classified here as a transition metal in Period 5 and Group 6. Molybdenum is the Period 5 Group 6 transition metal between chromium and tungsten. Its partly filled 4d shell supports multiple oxidation states, strong metallic bonding and diverse compound chemistry.
Key point: Mo is element 42; its periodic position and electron structure explain the rest of the page.
What is molybdenum used for?
Short answer: Major uses include alloy steels, high-temperature materials, catalysts and MoS₂ lubricants/materials.
Steel & superalloys: Molybdenum improves high-temperature strength, corrosion resistance and hardenability. Lubricants: MoS₂ serves as a low-friction solid lubricant, especially where oils are unsuitable. Molybdenum metal, molybdenum disulfide and molybdate chemistry are not interchangeable. One element can participate in very different bonding networks, material properties and biological roles.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
Where is molybdenum found?
Short answer: Commonly in molybdenite-bearing deposits and as a co-product of porphyry copper mining.
Molybdenum is commonly mined from molybdenite-bearing deposits or recovered as a co-product of copper mining. The Geography Explorer keeps natural occurrence separate from resources, industrial production and recycling, because those datasets answer different questions about molybdenum.
Key point: Natural occurrence, resources, production and recycling are different geography questions.
Is molybdenum a metal?
Short answer: Yes, it is a Group 6 transition metal.
This guide classifies Molybdenum as a transition metal. Its periodic position is Period 5, d-block, Group 6. Molybdenum is the Period 5 Group 6 transition metal between chromium and tungsten. Its partly filled 4d shell supports multiple oxidation states, strong metallic bonding and diverse compound chemistry.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
How many valence electrons does molybdenum have?
Short answer: The reference ground state is [Kr] 4d⁵5s¹; simple “valence electron” counting in transition metals depends on the chemistry being discussed.
The neutral-atom ground-state reference used on this page is [Kr] 4d⁵ 5s¹. This is an isolated-atom reference: bonding and ion formation can change which outer electrons are present or chemically active. The listed common oxidation-state context is +6, +5, +4, +3, +2, which helps connect the atomic configuration to ordinary chemistry without treating electron counting as a single universal rule.
Key point: Electron configuration is a ground-state atomic reference, not a literal picture of every compound.
Why is MoS₂ not the same as molybdenum metal?
Short answer: It is a compound with sulfur and a layered bonding structure, so its properties differ sharply from pure Mo.
This guide classifies Molybdenum as a transition metal. Its periodic position is Period 5, d-block, Group 6. Molybdenum is the Period 5 Group 6 transition metal between chromium and tungsten. Its partly filled 4d shell supports multiple oxidation states, strong metallic bonding and diverse compound chemistry.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
Scientific sources for Molybdenum
- Royal Society of Chemistry - Molybdenum
- NIST - Atomic Data for Molybdenum
- USGS - Mineral Commodity Summaries 2026
Questions to ask next about Molybdenum
A good element lesson should lead to the next useful question, not end after a list of facts.
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