Element / isotope identity
Atomic number, isotope identity and discovery evidence are experimentally/evaluatively grounded.
Electron configuration
Very-heavy-element configurations are theory/evaluation-led; ordinary elements use evaluated ground-state references.
Bulk material structure
The Hexagonal close-packed (HCP) reference is represented by a simplified teaching cell.
Phase / density data
Unknown values stay unknown; reported values are tied to the elemental material reference.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Hafnium (Hf)
Hafnium is element 72. This guide connects its periodic-table identity to evidence-aware structure, isotopes, uses, discovery and the search questions learners actually ask.
Hafnium atomic number, mass, electron configuration and key properties
Hafnium: quick answers
How many protons, neutrons and electrons does hafnium have?
Hafnium’s atomic number is 72, so every hafnium atom has 72 protons, and a neutral atom also has 72 electrons. Its most common natural isotope, hafnium-180, has 108 neutrons (other isotopes have different neutron counts).
What is the symbol for hafnium?
The chemical symbol for hafnium is Hf.
Is hafnium a solid, liquid or gas at room temperature?
Hafnium is a solid at room temperature (about 25 °C).
What family (group) is hafnium in?
Hafnium is a transition metal, in group 4, period 6 of the periodic table.
What is the electron configuration of hafnium?
The ground-state electron configuration of hafnium is [Xe] 4f¹⁴ 5d² 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.
72 protons define hafnium.
Ground-state/reference configuration frames atomic behavior; heavy-element predictions remain evidence-labelled.
Periodic position organizes trends without replacing element-specific evidence.
The teaching nucleus is one isotope, not the relative atomic mass.
Measured structures are visualized; unknown bulk structures stay unknown.
Hafnium in its period and family
Hafnium is element 72 in Period 6. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.
Hafnium Visual Lab
Explore Hf 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.
Hafnium in one minute
Atomic number 72 means every hafnium nucleus has 72 protons.
The ground-state/reference electron configuration is [Xe] 4f¹⁴ 5d² 6s².
The representative teaching isotope is ¹⁸⁰Hf.
Hafnium is chemically close to zirconium but has a much larger neutron-capture cross section. Elemental Hf, HfO₂ and hafnium-containing superalloys are different materials with different structures and functions.
Material structure status: Hexagonal close-packed (HCP).
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 32 · 10 · 2 electrons
Displayed orbitals are isolated-atom, nonrelativistic teaching probability models. They are not bulk-band structures, bonding orbitals or direct measured electron-density maps; relativistic effects become especially important for very heavy elements.
The viewer represents the reviewed Hexagonal close-packed (HCP) material reference for elemental Hafnium. It is a teaching model, not a refined crystallographic coordinate set or a model of every compound.. 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
Displayed orbitals are isolated-atom, nonrelativistic teaching probability models. They are not bulk-band structures, bonding orbitals or direct measured electron-density maps; relativistic effects become especially important for very heavy elements.
Where do I meet hafnium?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
Neutron-absorbing control components
This context uses Hafnium or a hafnium-containing material; the element and its compounds/isotopes are kept distinct.
Hafnium metal → engineered materials → evidence boundary
The same element can appear in very different materials; the page keeps elemental structure separate from compounds, alloys and isotope-specific applications.
Hexagonal close-packed (HCP)
Elemental Hafnium uses the reviewed ordinary structure shown in the Visual Lab.
Hafnium in periodic context
Compare nearby or family-related elements without treating a periodic trend as a substitute for element-specific evidence.
| Atomic number | 71 |
|---|---|
| Context | neighbor / series |
| Atomic number | 72 |
|---|---|
| Context | neighbor / series |
| Atomic number | 73 |
|---|---|
| Context | neighbor / series |
Hafnium 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 | 72 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 178.486 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Xe] 4f¹⁴ 5d² 6s² | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group 4 · Period 6 · d-block | Periodic-table placement | Evaluated |
| Electronegativity | 1.30 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ¹⁸⁰Hf | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Shiny silvery corrosion-resistant metal | Source-reviewed; see Sources below | Evaluated |
| Density | 13.3 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | Hexagonal close-packed (HCP) | The viewer represents the reviewed Hexagonal close-packed (HCP) material reference for elemental Hafnium. It is a teaching model, not a refined crystallographic coordinate set or a model of every compound. | Measured |
| Classification | Transition metal | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | The viewer represents the reviewed Hexagonal close-packed (HCP) material reference for elemental Hafnium. It is a teaching model, not a refined crystallographic coordinate set or a model of every compound. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 2506 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 4873 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, hafnium is treated as solid below 2506 K, liquid between the melting and boiling references, and gas above 4873 K. Solid-state allotropy is only shown where explicitly reviewed. | 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 | +4 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Hf³⁺ | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Hafnium is element 72 in Period 6. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ¹⁸⁰Hf | Reference teaching isotope | Mass number belongs to a specific isotope and is not the same thing as relative atomic mass. | Evaluated |
| Isotope evidence | Element-specific nuclear context | Half-life and decay properties are isotope-specific; the page does not generalize one isotope to all atoms. | Evaluated |
| Teaching nucleus | ¹⁸⁰Hf · 72 protons + 108 neutrons | Reference isotope used in the nucleus model | Reviewed |
Is Hafnium a solid, liquid or gas? State at temperature
At approximately standard pressure, hafnium is treated as solid below 2506 K, liquid between the melting and boiling references, and gas above 4873 K. Solid-state allotropy is only shown where explicitly reviewed.
Where on Earth is Hafnium found or produced?
Who discovered Hafnium, and when?
Dirk Coster and George de Hevesy identified hafnium in zirconium minerals in Copenhagen.
The element name and discovery story are part of the historical record; search-led questions are answered without turning history into scientific evidence for bulk properties.
Current use is described at the level supported by the element’s availability and evidence, with research-only elements kept research-only.
From source material to Hafnium applications: high-level material path
Hafnium enters supply chains through ores, by-products or specialized refining routes rather than through the educational structure shown here.
Industrial separation/refining produces metal or element-specific compounds; this guide does not provide operational extraction recipes.
The refined material is converted into the particular alloy, compound, device or catalyst needed by the application.
Recycling and recovery depend on host material and economics; application materials must not be confused with pure element.
What is hafnium used for?
Neutron-absorbing control components
Element-specific use context; compounds/alloys are distinguished from pure metal.
High-temperature alloys and plasma-electrode applications
Element-specific use context; compounds/alloys are distinguished from pure metal.
Hafnium oxide high-k dielectric materials in microelectronics
Element-specific use context; compounds/alloys are distinguished from pure metal.
Hafnium isotopes and natural abundance
¹⁸⁰Hf
Reference teaching isotopeMass number belongs to a specific isotope and is not the same thing as relative atomic mass.
Isotope evidence
Element-specific nuclear contextHalf-life and decay properties are isotope-specific; the page does not generalize one isotope to all atoms.
Five-question Hafnium check
What is Hafnium’s atomic number?
Which statement best describes the material evidence for Hafnium?
What is the safest rule for Hafnium uses?
Hafnium 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 hafnium?
Short answer: Hafnium is chemical element 72, symbol Hf, classified here as transition metal.
Atomic number 72 means every hafnium nucleus contains 72 protons. In the periodic table, Hafnium is classified here as a transition metal in Period 6 and Group 4. Hafnium is element 72 in Period 6. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.
Key point: Hf is element 72; its periodic position and electron structure explain the rest of the page.
What is the atomic number of hafnium?
Short answer: The atomic number is 72, meaning every hafnium nucleus has 72 protons.
Atomic number is defined by proton count, so 72 protons are what make an atom hafnium. A neutral hafnium atom also has 72 electrons, while isotopes can have different neutron counts without changing the element.
Key point: Atomic number = proton count.
What is the symbol for hafnium?
Short answer: The chemical symbol is Hf.
The symbol Hf is the standardized chemical abbreviation for element 72. In a chemical formula, Hf identifies hafnium atoms; a compound containing Hf is not automatically the same material as elemental hafnium.
Key point: Hf always identifies element 72.
What is hafnium used for?
Short answer: Hafnium is used in neutron-absorbing reactor components, high-temperature alloys, and hafnium-oxide dielectric materials in electronics.
Neutron-absorbing control components: Element-specific use context; compounds/alloys are distinguished from pure metal. High-temperature alloys and plasma-electrode applications: Element-specific use context; compounds/alloys are distinguished from pure metal. Hafnium is chemically close to zirconium but has a much larger neutron-capture cross section. Elemental Hf, HfO₂ and hafnium-containing superalloys are different materials with different structures and functions.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
What is the electron configuration of hafnium?
Short answer: The ground-state configuration is [Xe] 4f¹⁴ 5d² 6s².
The neutral-atom ground-state reference used on this page is [Xe] 4f¹⁴ 5d² 6s². 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 +4, 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 hafnium associated with zirconium?
Short answer: Hafnium and zirconium have very similar chemistry and commonly occur together in zirconium minerals, making them difficult to separate.
Hafnium is chemically close to zirconium but has a much larger neutron-capture cross section. Elemental Hf, HfO₂ and hafnium-containing superalloys are different materials with different structures and functions.
Key point: The mechanism matters: connect the observed behavior to electron structure, bonding, phase or the specific material form rather than memorizing the result alone.
Scientific sources for Hafnium
- Royal Society of Chemistry - Hafnium
- NIST - Atomic Weights and Isotopic Compositions
- IUPAC - Periodic Table of Elements
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