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Free Meitnerium student datasheetPrintable revision sheet with identity, structure, evidence notes, phase behavior, uses, isotopes and review prompts.
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Meitnerium atomic number, mass, electron configuration and key properties

Atomic number
109
Relative atomic mass
[278]
Electron configuration
[Rn] 5f¹⁴ 6d⁷ 7s²
Common oxidation states
Predicted transition-metal chemistry; bulk oxidation-state chemistry not established
Density
Unknown
Melting point
Unknown
Boiling point
Unknown
Ordinary crystal / bulk structure
Bulk crystal structure unknown
ClassificationTransition metal · superheavy
Reference isotope²⁷⁸Mt
State contextSuperheavy radioactive element known from only a few atoms
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

Meitnerium: quick answers

How many protons, neutrons and electrons does meitnerium have?

Meitnerium’s atomic number is 109, so every meitnerium atom has 109 protons, and a neutral atom also has 109 electrons. Meitnerium has no stable isotopes, so the neutron count depends on the isotope: meitnerium-278, featured on this page, has 169 neutrons.

What is the symbol for meitnerium?

The chemical symbol for meitnerium is Mt.

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

Meitnerium has only been made a few atoms at a time, so its state at room temperature is unknown.

What family (group) is meitnerium in?

Meitnerium is a transition metal (predicted), in group 9, period 7 of the periodic table.

What is the electron configuration of meitnerium?

The ground-state electron configuration of meitnerium is [Rn] 5f¹⁴ 6d⁷ 7s². This is a predicted configuration; it has not been measured.

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 misconceptionMeitnerium is known primarily through production and decay events. Periodic position motivates chemical predictions, but its macroscopic material properties remain unknown.
Periodic-table position

Meitnerium in its period and family

Meitnerium is element 109 in Period 7. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.

Interactive Visual Lab

Meitnerium Visual Lab

Explore Mt 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

1109 2[278] 3Mt 4[Rn] 5f¹⁴ 6d⁷ 7s² 5Meitnerium 6Bulk crystal structure unknown 7Superheavy radioa…
1Atomic numberNumber of protons
2Relative atomic massStandard value or bracketed reference mass
3Chemical symbolMt
4Electron configurationGround-state shorthand or evidence-labelled prediction
5Element nameMeitnerium
6Structure contextBulk crystal structure unknown
7Physical-state contextSuperheavy radioactive element known from only a few atoms

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

Meitnerium in one minute

01

Atomic number 109 means every meitnerium nucleus has 109 protons.

02

The ground-state/reference electron configuration is [Rn] 5f¹⁴ 6d⁷ 7s².

03

The representative teaching isotope is ²⁷⁸Mt.

04

Meitnerium is known primarily through production and decay events. Periodic position motivates chemical predictions, but its macroscopic material properties remain unknown.

05

Material structure status: Bulk crystal structure unknown.

Atomic structure teaching model

²⁷⁸Mt nucleus · neutral Mt

109 p⁺ · 169 n⁰
Nucleus modelNucleon-count teaching view
109 p⁺ + 169 n⁰²⁷⁸Mt · 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 · 15 · 2 electrons

n=12
n=28
n=318
n=432
n=532
n=615
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 unknown

No defensible macroscopic crystal lattice is displayed for Meitnerium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.
Bulk crystal structure unknownNo defensible macroscopic crystal lattice is displayed for Meitnerium. 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 Meitnerium. 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

6d z² 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 meitnerium?

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 Meitnerium or a meitnerium-containing material; the element and its compounds/isotopes are kept distinct.

1982Peter Armbruster, Gottfried Münzenberg and colleagues at GSI produced element 109; it was named for physicist Lise Meitner.
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

Meitnerium 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 number109Source-reviewed; see Sources belowEvaluated
Relative atomic mass[278]Source-reviewed; see Sources belowEvaluated
²⁷⁸MtReference 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 nucleus²⁷⁸Mt · 109 protons + 169 neutronsReference isotope used in the nucleus modelReviewed
PropertyValueContext / provenanceEvidence
Ground-state electron configuration[Rn] 5f¹⁴ 6d⁷ 7s²Source-reviewed; see Sources belowPredicted
Group / period / blockGroup 9 · Period 7 · d-blockPeriodic-table placementEvaluated
ElectronegativityUnknownSource-reviewed; see Sources belowUnknown
Common oxidation statesPredicted transition-metal chemistry; bulk oxidation-state chemistry not establishedSource-reviewed; see Sources belowPredicted
PropertyValueContext / provenanceEvidence
²⁷⁸MtReference 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 nucleus²⁷⁸Mt · 109 protons + 169 neutronsReference isotope used in the nucleus modelReviewed
PropertyValueContext / provenanceEvidence
Current useScientific research onlyNo commercial bulk use is implied.Reviewed
GeographyDiscovery, naming and research context onlyNo natural-resource map is appropriate.Reviewed
Safety boundaryNon-operational educational contextNo synthesis settings or material-access guidance.Reviewed
PropertyValueContext / provenanceEvidence
DensityUnknownSource-reviewed; see Sources belowUnknown
Material / molecular structureBulk crystal structure unknownNo defensible macroscopic crystal lattice is displayed for Meitnerium. Nuclear/atomic evidence and theory are kept separate from unmeasured bulk material properties.Unknown
Melting / transition referenceUnknownSource-reviewed; see Sources belowUnknown
Boiling / gas referenceUnknownSource-reviewed; see Sources belowUnknown
Common oxidation statesPredicted transition-metal chemistry; bulk oxidation-state chemistry not establishedSource-reviewed; see Sources belowPredicted
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 Meitnerium. 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 Meitnerium a solid, liquid or gas? State at temperature

No measured ordinary melting or boiling point is asserted. The phase track remains visible as an evidence-limited teaching view rather than inventing macroscopic transitions.

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

Where on Earth is Meitnerium found or produced?

World map
Darmstadt, GermanyRSC historical context · historical
Discovery and history

Who discovered Meitnerium, and when?

1982

Peter Armbruster, Gottfried Münzenberg and colleagues at GSI produced element 109; it was named for physicist Lise Meitner.

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 meitnerium used for?

Scientific research only

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

Nuclear-decay and superheavy-element studies

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

Isotopes

Meitnerium isotopes and natural abundance

²⁷⁸Mt

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 Meitnerium check

What is Meitnerium’s atomic number?

Which statement best describes the material evidence for Meitnerium?

What is the safest rule for Meitnerium uses?

Questions answered

Meitnerium 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 meitnerium?

Short answer: The atomic number is 109, meaning every meitnerium nucleus has 109 protons.

Atomic number is defined by proton count, so 109 protons are what make an atom meitnerium. A neutral meitnerium atom also has 109 electrons, while isotopes can have different neutron counts without changing the element.

Key point: Atomic number = proton count.

What is the symbol for meitnerium?

Short answer: The chemical symbol is Mt.

The symbol Mt is the standardized chemical abbreviation for element 109. In a chemical formula, Mt identifies meitnerium atoms; a compound containing Mt is not automatically the same material as elemental meitnerium.

Key point: Mt always identifies element 109.

What is meitnerium?

Short answer: Meitnerium is element 109, symbol Mt, a synthetic superheavy Group 9 element.

Atomic number 109 means every meitnerium nucleus contains 109 protons. In the periodic table, Meitnerium is classified here as a transition metal · superheavy in Period 7 and Group 9. Meitnerium is element 109 in Period 7. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.

Key point: Mt is element 109; its periodic position and electron structure explain the rest of the page.

What is meitnerium used for?

Short answer: It is used only for scientific research.

Scientific research only: Research-only context; no operational production or handling guidance. Nuclear-decay and superheavy-element studies: Research-only context; no operational production or handling guidance. Meitnerium is known primarily through production and decay events. Periodic position motivates chemical predictions, but its macroscopic material properties remain unknown.

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

Is meitnerium a metal?

Short answer: It is classified as a d-block transition element and expected to be metallic, but no macroscopic sample exists to measure ordinary bulk-metal properties.

This guide classifies Meitnerium as a transition metal · superheavy. Its periodic position is Period 7, d-block, Group 9. Meitnerium is element 109 in Period 7. Its d-block/series position provides useful periodic context, but element-specific experimental evidence takes priority over simple trend extrapolation.

Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.

Who was meitnerium named after?

Short answer: It was named for physicist Lise Meitner.

In 1982, Peter Armbruster, Gottfried Münzenberg and colleagues at GSI produced element 109; it was named for physicist Lise Meitner. 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 meitnerium look like?

Short answer: No ordinary macroscopic sample has been measured well enough to justify a definitive bulk appearance or crystal-lattice claim on this page.

The ordinary elemental-material description used here is: Superheavy radioactive element known from only a few atoms. No defensible macroscopic crystal lattice is displayed for Meitnerium. 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 Meitnerium

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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