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Free Nobelium student datasheetPrintable revision sheet with identity, structure, evidence notes, phase behavior, uses, isotopes and review prompts.
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Instant reference

Nobelium atomic number, mass, electron configuration and key properties

Atomic number
102
Relative atomic mass
[259]
Electron configuration
[Rn] 5f¹⁴ 7s²
Common oxidation states
+2, +3
Density
Unknown
Melting point
1100 K (reported reference)
Boiling point
Unknown
Ordinary crystal / bulk structure
Bulk crystal structure not experimentally established
ClassificationActinide
Reference isotope²⁵⁹No
State contextRadioactive synthetic actinide; only atom-scale quantities have been made
Evidence noteAtomic identity and source-reviewed reference values are separated from predictions. Search demand shapes headings and FAQs but never overrides scientific evidence; unknown bulk structure/density/phase values remain visibly unknown.
Quick answers

Nobelium: quick answers

How many protons, neutrons and electrons does nobelium have?

Nobelium’s atomic number is 102, so every nobelium atom has 102 protons, and a neutral atom also has 102 electrons. Nobelium has no stable isotopes, so the neutron count depends on the isotope: nobelium-259, featured on this page, has 157 neutrons.

What is the symbol for nobelium?

The chemical symbol for nobelium is No.

Is nobelium a solid, liquid or gas at room temperature?

Nobelium has only ever been made in tiny amounts, so its state at room temperature has not been observed; it is expected to be a solid metal.

What family (group) is nobelium in?

Nobelium is an actinide, in period 7 (the f-block row shown below the main table) of the periodic table.

What is the electron configuration of nobelium?

The ground-state electron configuration of nobelium is [Rn] 5f¹⁴ 7s².

Connect the facts

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.

Common misconceptionNobelium is notable for accessible No²⁺ chemistry compared with neighboring actinides, but its bulk material properties remain inaccessible because only tiny atom counts are produced.
Periodic-table position

Nobelium in its period and family

Nobelium is element 102 in Period 7. Its f-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.

Interactive Visual Lab

Nobelium Visual Lab

Explore No 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.

Overview · structure · orbitals · real world
How to read an element tile

Every mark points to one exact feature

1102 2[259] 3No 4[Rn] 5f¹⁴ 7s² 5Nobelium 6Bulk crystal structure not experimentally established 7Radioactive synth…
1Atomic numberNumber of protons
2Relative atomic massStandard value or bracketed reference mass
3Chemical symbolNo
4Electron configurationGround-state shorthand or evidence-labelled prediction
5Element nameNobelium
6Structure contextBulk crystal structure not experimentally established
7Physical-state contextRadioactive synthetic actinide; only atom-scale quantities have been made

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.

Five things worth remembering

Nobelium in one minute

01

Atomic number 102 means every nobelium nucleus has 102 protons.

02

The ground-state/reference electron configuration is [Rn] 5f¹⁴ 7s².

03

The representative teaching isotope is ²⁵⁹No.

04

Nobelium is notable for accessible No²⁺ chemistry compared with neighboring actinides, but its bulk material properties remain inaccessible because only tiny atom counts are produced.

05

Material structure status: Bulk crystal structure not experimentally established.

Atomic structure teaching model

²⁵⁹No nucleus · neutral No

102 p⁺ · 157 n⁰
Nucleus modelNucleon-count teaching view
102 p⁺ + 157 n⁰²⁵⁹No · schematic nucleus, not a literal nuclear geometry
Electron-count schematicPrincipal-shell populations

Shell rings organize electron counts. They are not electron trajectories or orbital shapes.

Nucleus, shell count and material structure are deliberately separated so one picture is not mistaken for another.
Connect picture → chemistry

2 · 8 · 18 · 32 · 32 · 8 · 2 electrons

n=12
n=28
n=318
n=432
n=532
n=68
n=72
Why this electron pattern matters

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.

Teaching boundary: the nucleus uses colored spheres to make proton/neutron counts visible; the shell diagram only summarizes principal-shell populations. Neither is a literal picture of electron motion.
Material / molecular structure viewer

Bulk crystal structure not experimentally established

No defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.
Bulk crystal structure not experimentally establishedNo defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.
What are you seeing?

No defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.. 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.
Probability-cloud teaching model

5f z³-type orbital

One-electron teaching approximation; dots represent sampled probability density, not individual electrons.
Interpretation

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.

Important: The cloud includes the expected nodal pattern for the named nonrelativistic orbital where applicable. Phase colors are not electric charge. For heavy and superheavy elements, relativistic/many-electron effects make these only teaching approximations.
Real-world archive

Where do I meet nobelium?

Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.

One
Scientific research only

Scientific research only

This context uses Nobelium or a nobelium-containing material; the element and its compounds/isotopes are kept distinct.

1960sDiscovery claims were disputed; IUPAC ultimately credited work at the Joint Institute for Nuclear Research in Dubna.
Naming / contextThe 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.
TodayCurrent use is described at the level supported by the element’s availability and evidence, with research-only elements kept research-only.
Evidence principleAtomic identity and source-reviewed reference values are separated from predictions. Search demand shapes headings and FAQs but never overrides scientific evidence; unknown bulk structure/density/phase values remain visibly unknown.
Signature science

Evidence ladder: nucleus → atom-scale chemistry → unknown bulk material

For scarce synthetic heavy elements, different claims have very different evidence strength.

Evaluated

Nuclear identity

Production/decay evidence establishes the element and specific isotopes.

Reference properties

Nobelium 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.

PropertyValueContext / provenanceEvidence
Atomic number102Source-reviewed; see Sources belowEvaluated
Relative atomic mass[259]Source-reviewed; see Sources belowEvaluated
Ground-state electron configuration[Rn] 5f¹⁴ 7s²Source-reviewed; see Sources belowEvaluated
Group / period / blockGroup Actinide · Period 7 · f-blockPeriodic-table placementEvaluated
ElectronegativityUnknownSource-reviewed; see Sources belowUnknown
Reference isotope²⁵⁹NoSource-reviewed; see Sources belowEvaluated
PropertyValueContext / provenanceEvidence
State contextRadioactive synthetic actinide; only atom-scale quantities have been madeSource-reviewed; see Sources belowEvaluated
DensityUnknownSource-reviewed; see Sources belowUnknown
Material / molecular structureBulk crystal structure not experimentally establishedNo defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.Unknown
ClassificationActinidePeriodic-table / chemistry classificationEvaluated
Structure-model scopeNo defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.Teaching visualization; exact crystallographic coordinates are not implied unless stated.Reviewed
PropertyValueContext / provenanceEvidence
Melting / transition reference1100 K (reported reference)Source-reviewed; see Sources belowEvaluated
Boiling / gas referenceUnknownSource-reviewed; see Sources belowUnknown
Phase-path contextA melting reference of 1100 K (reported reference) is reported for teaching context, while an ordinary boiling point is not established here. The page does not infer a precise gas transition from theory.Shared phase registry drives the slider, regions and markers.Evaluated
Condition warningTemperature and pressure define phase behavior; purity/allotropy may matter.Teaching condition statementReviewed
PropertyValueContext / provenanceEvidence
Common oxidation states+2, +3Source-reviewed; see Sources belowEvaluated
Ion / common ion contextNo³⁺Source-reviewed; see Sources belowEvaluated
Periodic chemistry contextNobelium is element 102 in Period 7. Its f-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.Element-specific interpretationReviewed
Chemistry cautionElemental form, ions and compounds are distinct chemical objects.Interpretive teaching ruleReviewed
PropertyValueContext / provenanceEvidence
²⁵⁹NoReference teaching isotopeMass number belongs to a specific isotope and is not the same thing as relative atomic mass.Evaluated
Isotope evidenceElement-specific nuclear contextHalf-life and decay properties are isotope-specific; the page does not generalize one isotope to all atoms.Evaluated
Teaching nucleus²⁵⁹No · 102 protons + 157 neutronsReference isotope used in the nucleus modelReviewed
PropertyValueContext / provenanceEvidence
Page evidence noteAtomic identity and source-reviewed reference values are separated from predictions. Search demand shapes headings and FAQs but never overrides scientific evidence; unknown bulk structure/density/phase values remain visibly unknown.Evidence summary for this guideReviewed
Structure evidenceNo defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.Measured structure, labelled schematic, prediction or explicit unknown as applicable.Reviewed
Map evidence ruleReal pins are reviewed examples; conceptual layers are used when pins would mislead.Geography Explorer 2.0Reviewed
Source set3 primary/reference links listed belowOpen the Sources section for the actual references.Reviewed
Temperature explorer

Is Nobelium a solid, liquid or gas? State at temperature

A melting reference of 1100 K (reported reference) is reported for teaching context, while an ordinary boiling point is not established here. The page does not infer a precise gas transition from theory.

Temperature293 K
Move the slider
The shared site-wide phase model controls the track, markers and readout.
Geography and evidence

Where on Earth is Nobelium found or produced?

World map
Dubna, RussiaRSC historical context · historical
Discovery and history

Who discovered Nobelium, and when?

1960s

Discovery claims were disputed; IUPAC ultimately credited work at the Joint Institute for Nuclear Research in Dubna.

Naming / context

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.

Today

Current use is described at the level supported by the element’s availability and evidence, with research-only elements kept research-only.

Process / synthesis context

Research production context: high-level, non-operational

1

The element is produced or isolated only in specialized research/nuclear settings; this page intentionally omits operational synthesis, target, beam, separation, handling and access instructions.

2

Experimental identity is established from nuclear decay, spectroscopy and/or atom-scale chemistry appropriate to the element.

3

Any chemical or material inference is labelled by evidence strength; unmeasured bulk properties are not converted into visual facts.

4

Research use is described conceptually, with isotope-specific claims kept distinct from the element as a whole.

Safety boundary: This page is educational and non-operational. It provides no radioactive-material production, separation, source-preparation, handling or access instructions.
Real-world applications

What is nobelium used for?

Scientific research only

Research-only context; no operational production or handling guidance.

Heavy-element and actinide chemistry studies

Research-only context; no operational production or handling guidance.

Isotopes

Nobelium isotopes and natural abundance

²⁵⁹No

Reference teaching isotope

Mass number belongs to a specific isotope and is not the same thing as relative atomic mass.

Isotope evidence

Element-specific nuclear context

Half-life and decay properties are isotope-specific; the page does not generalize one isotope to all atoms.

Learn it, don’t just read it

Five-question Nobelium check

What is Nobelium’s atomic number?

Which statement best describes the material evidence for Nobelium?

What is the safest rule for Nobelium uses?

Questions answered

Nobelium 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 the atomic number of nobelium?

Short answer: The atomic number is 102, meaning every nobelium nucleus has 102 protons.

Atomic number is defined by proton count, so 102 protons are what make an atom nobelium. A neutral nobelium atom also has 102 electrons, while isotopes can have different neutron counts without changing the element.

Key point: Atomic number = proton count.

What is the symbol for nobelium?

Short answer: The chemical symbol is No.

The symbol No is the standardized chemical abbreviation for element 102. In a chemical formula, No identifies nobelium atoms; a compound containing No is not automatically the same material as elemental nobelium.

Key point: No always identifies element 102.

What is nobelium?

Short answer: Nobelium is element 102, symbol No, a synthetic radioactive actinide.

Atomic number 102 means every nobelium nucleus contains 102 protons. In the periodic table, Nobelium is classified here as an actinide in Period 7 and Group Actinide. Nobelium is element 102 in Period 7. Its f-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.

Key point: No is element 102; its periodic position and electron structure explain the rest of the page.

What is nobelium used for?

Short answer: Nobelium has no use outside scientific research.

Scientific research only: Research-only context; no operational production or handling guidance. Heavy-element and actinide chemistry studies: Research-only context; no operational production or handling guidance. Nobelium is notable for accessible No²⁺ chemistry compared with neighboring actinides, but its bulk material properties remain inaccessible because only tiny atom counts are produced.

Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.

Who was nobelium named after?

Short answer: It was named after Alfred Nobel.

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.

Key point: Element names record scientific history; the name itself does not determine the element’s chemistry.

What does nobelium look like?

Short answer: Only a few atoms have been made; no measured macroscopic bulk crystal structure is presented.

The ordinary elemental-material description used here is: Radioactive synthetic actinide; only atom-scale quantities have been made. No defensible macroscopic crystal lattice is displayed for Nobelium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.

Key point: Elemental appearance can differ from the colors of its ions, compounds, oxide films or host materials.

Scientific sources and provenance

Scientific sources for Nobelium

Evidence rule: Atomic identity and source-reviewed reference values are separated from predictions. Search demand shapes headings and FAQs but never overrides scientific evidence; unknown bulk structure/density/phase values remain visibly unknown.
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