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.
Scandium (Sc)
Scandium is element 21, a light Group 3 transition metal whose 3d¹4s² atom, stable ⁴⁵Sc isotope and high-temperature HCP-to-BCC transition connect periodic trends to aluminium-scandium alloys and specialty lighting.
Scandium atomic number, mass, electron configuration and key properties
Scandium: quick answers
How many protons, neutrons and electrons does scandium have?
Scandium’s atomic number is 21, so every scandium atom has 21 protons, and a neutral atom also has 21 electrons. Its most common natural isotope, scandium-45, has 24 neutrons (other isotopes have different neutron counts).
What is the symbol for scandium?
The chemical symbol for scandium is Sc.
Is scandium a solid, liquid or gas at room temperature?
Scandium is a solid at room temperature (about 25 °C).
What family (group) is scandium in?
Scandium is a transition metal, in group 3, period 4 of the periodic table.
What is the electron configuration of scandium?
The ground-state electron configuration of scandium is [Ar] 3d¹ 4s².
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.
21 protons define scandium.
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.
Scandium in its period and family
Scandium begins the 3d transition series in Period 4 and sits in Group 3 above yttrium. Its ground-state 3d¹4s² pattern and strong preference for Sc³⁺ make it chemically simpler than many neighboring transition metals.
Scandium Visual Lab
Explore Sc 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.
Scandium in one minute
Atomic number 21 means 21 protons.
Neutral Scandium has [Ar] 3d¹ 4s².
Its representative teaching isotope is ⁴⁵Sc.
Scandium is a metal, but its practical story is mostly about small additions and compounds rather than bulk scandium objects.
The ordinary material reference is hexagonal close-packed at room temperature.
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 9 · 2 electrons
The 3d_z2, 4s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Scandium materials.
Scandium is HCP near room temperature and transforms to BCC at high temperature before melting. The viewer shows the ordinary HCP teaching cell; the phase track carries the high-temperature transition.. 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 3d_z2, 4s visuals are isolated-atom probability teaching models. They do not depict electron bands, bonding orbitals or the crystal electronic structure of Scandium materials.
Where do I meet scandium?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
Alloys
Small scandium additions can strengthen selected aluminium alloys and influence grain structure.
Prediction → discovery → alloy effect
Scandium is a metal, but its practical story is mostly about small additions and compounds rather than bulk scandium objects. Its dominant +3 chemistry follows loss of the 4s and 3d valence electrons.
Eka-boron
Mendeleev predicted key properties before scandium was found.
Scandium in periodic context
Compare nearby or family-related elements without treating a trend as a substitute for element-specific evidence.
| Group | 3 |
|---|---|
| Period | 4 |
| Main ion | Sc³⁺ |
| Group | 3 |
|---|---|
| Period | 5 |
| Main ion | Y³⁺ |
| Group | 4 |
|---|---|
| Period | 4 |
| Metal | transition |
Scandium 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 | 21 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 44.956 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Ar] 3d¹ 4s² | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group 3 · Period 4 · d-block | Periodic-table placement | Evaluated |
| Electronegativity | 1.36 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ⁴⁵Sc | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Silvery transition metal | Source-reviewed; see Sources below | Evaluated |
| Density | 2.99 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | Hexagonal close-packed at room temperature | Scandium is HCP near room temperature and transforms to BCC at high temperature before melting. The viewer shows the ordinary HCP teaching cell; the phase track carries the high-temperature transition. | Measured |
| Classification | Transition metal | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | Scandium is HCP near room temperature and transforms to BCC at high temperature before melting. The viewer shows the ordinary HCP teaching cell; the phase track carries the high-temperature transition. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 1814 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 3109 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, scandium is HCP solid near room temperature, changes to a BCC solid near 1609 K, melts at 1814 K, and boils near 3109 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 |
|---|---|---|---|
| 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 | +3 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Sc³⁺ | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Scandium begins the 3d transition series in Period 4 and sits in Group 3 above yttrium. Its ground-state 3d¹4s² pattern and strong preference for Sc³⁺ make it chemically simpler than many neighboring transition metals. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ⁴⁵Sc | Stable natural isotope | Essentially all natural scandium. | Evaluated |
| Radioisotopes | Research/medical tracers | Artificial isotopes exist for research contexts. | Evaluated |
| Natural scandium | Single stable-isotope element | Relative atomic mass is therefore close to the ⁴⁵Sc isotope mass. | Evaluated |
| Teaching nucleus | ⁴⁵Sc · 21 protons + 24 neutrons | Reference isotope used in the nucleus model | Reviewed |
Is Scandium a solid, liquid or gas? State at temperature
At approximately standard pressure, scandium is HCP solid near room temperature, changes to a BCC solid near 1609 K, melts at 1814 K, and boils near 3109 K.
Where on Earth is Scandium found or produced?
Who discovered Scandium, and when?
Mendeleev predicted an element he called eka-boron from periodic trends.
Lars Fredrik Nilson identified scandium in Scandinavian mineral material.
Per Teodor Cleve recognized that scandium closely matched Mendeleev’s eka-boron prediction.
Scandium is used in small-volume, high-value alloy and specialty-material applications.
From source material to Scandium applications: high-level material path
Scandium is recovered from selected scandium-rich ores, tailings or process streams rather than from native scandium metal.
Separation/refining produces scandium compounds or high-purity metal feedstock.
Small scandium additions or compounds are converted into alloy, lighting or research materials.
Recycling opportunities depend on the host material and economics; no extraction recipe is provided.
What is scandium used for?
Aluminium alloys
Small Sc additions can refine microstructure and improve selected alloy properties.
Metal-halide lamps
Scandium-containing compounds have been used to tune lamp spectra.
Ceramics & research
Sc compounds appear in specialized ceramics, catalysts and research materials.
Teaching
Sc provides a clean Group 3 example linking d-block configuration to +3 chemistry.
Scandium isotopes and natural abundance
⁴⁵Sc
Stable natural isotopeEssentially all natural scandium.
Radioisotopes
Research/medical tracersArtificial isotopes exist for research contexts.
Natural scandium
Single stable-isotope elementRelative atomic mass is therefore close to the ⁴⁵Sc isotope mass.
Five-question Scandium check
What is Scandium’s atomic number?
Which classification best fits Scandium?
What is the representative teaching isotope?
Which statement respects the material evidence?
Which rule should guide real-world uses?
Scandium 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 scandium?
Short answer: Scandium is chemical element 21, a Group 3 transition metal.
Atomic number 21 means every scandium nucleus contains 21 protons. In the periodic table, Scandium is classified here as a transition metal in Period 4 and Group 3. Scandium begins the 3d transition series in Period 4 and sits in Group 3 above yttrium. Its ground-state 3d¹4s² pattern and strong preference for Sc³⁺ make it chemically simpler than many neighboring transition metals.
Key point: Sc is element 21; its periodic position and electron structure explain the rest of the page.
What is scandium used for?
Short answer: It is used mainly in small additions to selected aluminium alloys and in specialized scandium compounds.
Aluminium alloys: Small Sc additions can refine microstructure and improve selected alloy properties. Metal-halide lamps: Scandium-containing compounds have been used to tune lamp spectra. Scandium is a metal, but its practical story is mostly about small additions and compounds rather than bulk scandium objects. Its dominant +3 chemistry follows loss of the 4s and 3d valence electrons.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
Is scandium a metal?
Short answer: Yes. It is a silvery transition metal.
This guide classifies Scandium as a transition metal. Its periodic position is Period 4, d-block, Group 3. Scandium begins the 3d transition series in Period 4 and sits in Group 3 above yttrium. Its ground-state 3d¹4s² pattern and strong preference for Sc³⁺ make it chemically simpler than many neighboring transition metals.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
Where is scandium found?
Short answer: Scandium is dispersed in many minerals and is usually recovered from specialized ores or process streams rather than mined as a native metal.
Scandium is recovered from selected scandium-rich ores, tailings or process streams rather than from native scandium metal. The Geography Explorer keeps natural occurrence separate from resources, industrial production and recycling, because those datasets answer different questions about scandium.
Key point: Natural occurrence, resources, production and recycling are different geography questions.
Who discovered scandium?
Short answer: Lars Fredrik Nilson identified it in 1879.
In 1869, Mendeleev predicted an element he called eka-boron from periodic trends. In 1879, Lars Fredrik Nilson identified scandium in Scandinavian mineral material.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
How many valence electrons does scandium have?
Short answer: Its ground-state configuration ends 3d¹4s²; introductory treatments often discuss three outer/d electrons that support Sc³⁺.
The neutral-atom ground-state reference used on this page is [Ar] 3d¹ 4s². 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 +3, 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.
What is scandium’s symbol?
Short answer: Sc.
The symbol Sc is the standardized chemical abbreviation for element 21. In a chemical formula, Sc identifies scandium atoms; a compound containing Sc is not automatically the same material as elemental scandium.
Key point: Sc always identifies element 21.
Scientific sources for Scandium
- Royal Society of Chemistry - Scandium
- NIST - Atomic Weights and Isotopic Compositions
- USGS - Mineral Commodity Summaries 2026
Questions to ask next about Scandium
A good element lesson should lead to the next useful question, not end after a list of facts.
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