Atomic / phase data
Reference atomic and phase values are source-reviewed.
Material structure
The ordinary elemental structure is measured; the viewer is a teaching representation.
Element vs material uses
Uses distinguish elemental metal from compounds, alloys, dopants or medical formulations.
Geography
Discovery/supply context is selective and does not fabricate deposits or facilities.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Cerium (Ce)
Cerium is element 58, a reactive lanthanide whose accessible Ce³⁺/Ce⁴⁺ redox chemistry and unusually rich solid-state allotropy connect the periodic table to catalysts, glass polishing, lighter flints and oxygen-storage materials.
Cerium atomic number, mass, electron configuration and key properties
Cerium: quick answers
How many protons, neutrons and electrons does cerium have?
Cerium’s atomic number is 58, so every cerium atom has 58 protons, and a neutral atom also has 58 electrons. Its most common natural isotope, cerium-140, has 82 neutrons (other isotopes have different neutron counts).
What is the symbol for cerium?
The chemical symbol for cerium is Ce.
Is cerium a solid, liquid or gas at room temperature?
Cerium is a solid at room temperature (about 25 °C).
What family (group) is cerium in?
Cerium is a lanthanide, in period 6 (the f-block row shown below the main table) of the periodic table.
What is the electron configuration of cerium?
The ground-state electron configuration of cerium is [Xe] 4f¹ 5d¹ 6s².
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.
58 protons define cerium.
The ground-state configuration frames atomic and chemical behavior.
Periodic position organizes recurring chemistry and trends.
The teaching nucleus is one isotope, not the relative atomic mass.
Phase claims preserve source-reviewed evidence and allotrope context.
Cerium in its period and family
Cerium is the second lanthanide and can access both Ce³⁺ and Ce⁴⁺ unusually readily. That redox flexibility, combined with complex 4f/5d electronic behavior, makes cerium stand out from many neighboring lanthanides.
Cerium Visual Lab
Explore Ce across the teaching nucleus, isolated-atom orbitals, evidence-aware material structure and temperature/evidence views, then connect those models to uses, isotopes, search-led questions and source-backed context.
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.
Cerium in one minute
Atomic number 58 means 58 protons.
Neutral Cerium has [Xe] 4f¹ 5d¹ 6s².
Its representative teaching isotope is ¹⁴⁰Ce.
Cerium (Ce, 58) is not curium (Cm, 96).
The ordinary material reference is γ-ce face-centred cubic near room temperature; multiple allotropes.
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 19 · 9 · 2 electrons
The 4f_xyz, 5d_z2, 6s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Cerium materials.
Cerium has unusually complex allotropy. Around room temperature γ-Ce is FCC; β-Ce can appear below roughly 283 K and δ-Ce becomes BCC near 998 K before melting. The viewer shows room-temperature γ-Ce, while the phase track makes the allotrope changes explicit.. 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 4f_xyz, 5d_z2, 6s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Cerium materials.
Where do I meet cerium?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
Catalysts
CeO₂ and related cerium oxides participate in automotive and industrial oxidation/reduction catalysis.
Ce³⁺ ⇄ Ce⁴⁺ → oxygen storage
Cerium (Ce, 58) is not curium (Cm, 96). Their similar names hide completely different chemistry: cerium is a naturally abundant lanthanide used in catalysts and polishing materials, while curium is a radioactive synthetic/actinide element.
Ce³⁺ / Ce⁴⁺
Cerium changes oxidation state readily compared with many lanthanides.
Cerium in periodic context
Compare nearby or family-related elements without treating a trend as a substitute for element-specific evidence.
| Series | lanthanide |
|---|---|
| Common state | +3 |
| Series | lanthanide |
|---|---|
| States | +3/+4 |
| Series | lanthanide |
|---|---|
| Common state | +3 |
Cerium 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 | 58 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 140.116 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Xe] 4f¹ 5d¹ 6s² | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group Lanthanide · Period 6 · f-block | Periodic-table placement | Evaluated |
| Electronegativity | 1.12 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ¹⁴⁰Ce | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Soft gray reactive lanthanide metal | Source-reviewed; see Sources below | Evaluated |
| Density | 6.77 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | γ-Ce face-centred cubic near room temperature; multiple allotropes | Cerium has unusually complex allotropy. Around room temperature γ-Ce is FCC; β-Ce can appear below roughly 283 K and δ-Ce becomes BCC near 998 K before melting. The viewer shows room-temperature γ-Ce, while the phase track makes the allotrope changes explicit. | Measured |
| Classification | Lanthanide | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | Cerium has unusually complex allotropy. Around room temperature γ-Ce is FCC; β-Ce can appear below roughly 283 K and δ-Ce becomes BCC near 998 K before melting. The viewer shows room-temperature γ-Ce, while the phase track makes the allotrope changes explicit. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 1072 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 3716 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | A simplified approximately standard-pressure path shows β-Ce (DHCP) below about 283 K, γ-Ce (FCC) from about 283 to 998 K, δ-Ce (BCC) from about 998 K to the 1072 K melting point, then liquid to about 3716 K. | 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 |
|---|---|---|---|
| Common oxidation states | +3, +4 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Ce³⁺ | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Cerium is the second lanthanide and can access both Ce³⁺ and Ce⁴⁺ unusually readily. That redox flexibility, combined with complex 4f/5d electronic behavior, makes cerium stand out from many neighboring lanthanides. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ¹⁴⁰Ce | Stable natural isotope | Most abundant natural cerium isotope. | Evaluated |
| ¹⁴²Ce | Very long-lived natural isotope | Radioactive only on immense timescales. | Evaluated |
| ¹³⁶Ce + ¹³⁸Ce | Stable natural isotopes | Minor components of natural cerium. | Evaluated |
| Teaching nucleus | ¹⁴⁰Ce · 58 protons + 82 neutrons | Reference isotope used in the nucleus model | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Page evidence note | Atomic identity, reference values and ordinary structures are source-reviewed. Material viewers are teaching representations, not crystallographic refinements. Search demand never overrides measured/evaluated evidence or compound-vs-element distinctions. | Evidence summary for this guide | Reviewed |
| Structure evidence | Cerium has unusually complex allotropy. Around room temperature γ-Ce is FCC; β-Ce can appear below roughly 283 K and δ-Ce becomes BCC near 998 K before melting. The viewer shows room-temperature γ-Ce, while the phase track makes the allotrope changes explicit. | Measured structure, labelled schematic, prediction or explicit unknown as applicable. | Reviewed |
| Map evidence rule | Real pins are reviewed examples; conceptual layers are used when pins would mislead. | Geography Explorer 2.0 | Reviewed |
| Source set | 3 primary/reference links listed below | Open the Sources section for the actual references. | Reviewed |
Is Cerium a solid, liquid or gas? State at temperature
A simplified approximately standard-pressure path shows β-Ce (DHCP) below about 283 K, γ-Ce (FCC) from about 283 to 998 K, δ-Ce (BCC) from about 998 K to the 1072 K melting point, then liquid to about 3716 K.
Where on Earth is Cerium found or produced?
Who discovered Cerium, and when?
Cerium was discovered independently by Berzelius and Hisinger in Sweden and by Klaproth in Germany.
The name honored Ceres, the recently discovered asteroid/dwarf planet.
Rare-earth separation gradually clarified cerium chemistry and compounds.
Ceria became important in catalysts, polishing and oxygen-storage materials.
From source material to Cerium applications: high-level material path
Rare-earth ores are processed into mixed rare-earth concentrates.
Cerium can be separated and oxidized/reduced between Ce³⁺ and Ce⁴⁺ chemical forms depending on the product route.
Ceria, mischmetal and other materials are manufactured for catalysts, polishing and specialty applications.
Recycling paths depend on the host product; the guide provides no industrial separation recipe.
What is cerium used for?
Catalytic converters
Ceria supports oxygen-storage and catalytic functions in exhaust-treatment materials.
Glass polishing
CeO₂ is widely used as a polishing abrasive/chemical aid.
Ferrocerium
Cerium-rich alloys generate sparks in lighter “flints.”
Glass & ceramics
Cerium compounds modify color, UV response and redox properties in selected materials.
Cerium isotopes and natural abundance
¹⁴⁰Ce
Stable natural isotopeMost abundant natural cerium isotope.
¹⁴²Ce
Very long-lived natural isotopeRadioactive only on immense timescales.
¹³⁶Ce + ¹³⁸Ce
Stable natural isotopesMinor components of natural cerium.
Five-question Cerium check
What is Cerium’s atomic number?
Which classification best fits Cerium?
What is the representative teaching isotope?
Which statement respects the material evidence?
Which rule should guide real-world uses?
Cerium 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 cerium?
Short answer: Cerium is chemical element 58, a lanthanide metal.
Atomic number 58 means every cerium nucleus contains 58 protons. In the periodic table, Cerium is classified here as a lanthanide in Period 6 and Group Lanthanide. Cerium is the second lanthanide and can access both Ce³⁺ and Ce⁴⁺ unusually readily. That redox flexibility, combined with complex 4f/5d electronic behavior, makes cerium stand out from many neighboring lanthanides.
Key point: Ce is element 58; its periodic position and electron structure explain the rest of the page.
Is cerium a metal?
Short answer: Yes. It is a reactive gray lanthanide metal.
This guide classifies Cerium as a lanthanide. Its periodic position is Period 6, f-block, Group Lanthanide. Cerium is the second lanthanide and can access both Ce³⁺ and Ce⁴⁺ unusually readily. That redox flexibility, combined with complex 4f/5d electronic behavior, makes cerium stand out from many neighboring lanthanides.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
What is cerium used for?
Short answer: Cerium compounds are important in catalysts, glass polishing and specialized glass; cerium-rich alloys are used in lighter flints.
Catalytic converters: Ceria supports oxygen-storage and catalytic functions in exhaust-treatment materials. Glass polishing: CeO₂ is widely used as a polishing abrasive/chemical aid. Cerium (Ce, 58) is not curium (Cm, 96). Their similar names hide completely different chemistry: cerium is a naturally abundant lanthanide used in catalysts and polishing materials, while curium is a radioactive synthetic/actinide element.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
What is the difference between cerium and curium?
Short answer: Cerium is Ce, element 58, a lanthanide. Curium is Cm, element 96, a radioactive actinide.
Cerium (Ce, 58) is not curium (Cm, 96). Their similar names hide completely different chemistry: cerium is a naturally abundant lanthanide used in catalysts and polishing materials, while curium is a radioactive synthetic/actinide element. Ferrocerium Cerium-rich alloys generate sparks in lighter “flints.”.
Key point: The pure element, its ions, compounds and alloys are different materials and should not be treated as interchangeable.
Where is cerium found?
Short answer: It occurs in rare-earth minerals such as monazite and bastnäsite, not usually as native metal.
Rare-earth ores are processed into mixed rare-earth concentrates. 19th century Rare-earth separation gradually clarified cerium chemistry and compounds.
Key point: Natural occurrence, resources, production and recycling are different geography questions.
Who discovered cerium?
Short answer: It was independently discovered in 1803 by Berzelius/Hisinger and by Klaproth.
In 1803, Cerium was discovered independently by Berzelius and Hisinger in Sweden and by Klaproth in Germany. In 1803, The name honored Ceres, the recently discovered asteroid/dwarf planet.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
What is cerium’s symbol?
Short answer: Ce.
The symbol Ce is the standardized chemical abbreviation for element 58. In a chemical formula, Ce identifies cerium atoms; a compound containing Ce is not automatically the same material as elemental cerium.
Key point: Ce always identifies element 58.
Scientific sources for Cerium
- Royal Society of Chemistry - Cerium
- NIST - Atomic Weights and Isotopic Compositions
- USGS - Mineral Commodity Summaries 2026
Questions to ask next about Cerium
A good element lesson should lead to the next useful question, not end after a list of facts.
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