Atomic / phase data
Reference atomic and phase values are source-reviewed.
Material structure
The ordinary elemental structure is measured/reviewed; the viewer is a teaching representation.
Element vs material uses
Uses distinguish elemental metal from compounds, alloys, doped hosts or isotope-specific systems.
Geography
Discovery/supply context is selective and does not fabricate deposits, facilities or inventories.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Ruthenium (Ru)
Ruthenium is element 44, a rare platinum-group transition metal. Its HCP metal, flexible oxidation chemistry and durable compounds connect the periodic table to chip resistors, electrical contacts, catalysis and electrochemical coatings.
Ruthenium atomic number, mass, electron configuration and key properties
Ruthenium: quick answers
How many protons, neutrons and electrons does ruthenium have?
Ruthenium’s atomic number is 44, so every ruthenium atom has 44 protons, and a neutral atom also has 44 electrons. Its most common natural isotope, ruthenium-102, has 58 neutrons (other isotopes have different neutron counts).
What is the symbol for ruthenium?
The chemical symbol for ruthenium is Ru.
Is ruthenium a solid, liquid or gas at room temperature?
Ruthenium is a solid at room temperature (about 25 °C).
What family (group) is ruthenium in?
Ruthenium is a transition metal, in group 8, period 5 of the periodic table.
What is the electron configuration of ruthenium?
The ground-state electron configuration of ruthenium is [Kr] 4d⁷ 5s¹.
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.
44 protons define ruthenium.
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 material context.
Ruthenium in its period and family
Ruthenium sits in Group 8, Period 5 between technetium and rhodium, below iron and above osmium. Its partially filled 4d shell supports multiple oxidation states and rich coordination and catalytic chemistry.
Ruthenium Visual Lab
Explore Ru 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.
Ruthenium in one minute
Atomic number 44 means every ruthenium nucleus has 44 protons.
Neutral Ruthenium has the ground-state configuration [Kr] 4d⁷ 5s¹.
The representative teaching isotope is ¹⁰²Ru.
Ruthenium metal, ruthenium oxide and “ruthenium red” are not the same material.
The ordinary material reference is Hexagonal close-packed (HCP).
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 15 · 1 electrons
The displayed d and s orbitals are isolated-atom probability teaching models. They are not metallic bands, bonding orbitals or measured electron-density maps of the bulk material.
Ordinary ruthenium metal is HCP. The viewer is a conventional close-packed teaching cell and does not represent RuO₂, RuO₄ or coordination compounds.. 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 displayed d and s orbitals are isolated-atom probability teaching models. They are not metallic bands, bonding orbitals or measured electron-density maps of the bulk material.
Where do I meet ruthenium?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
Chip resistors
Ruthenium-containing oxide materials are widely used in thick-film resistor systems; the functional material is not simply a block of Ru metal.
4d chemistry → durable compounds → electronics/catalysis
Elemental ruthenium metal, RuO₂ coatings, volatile RuO₄ and “ruthenium red” are different chemical objects. The page keeps them separate so compound search interest does not blur their structures or hazards.
HCP Ru
Dense platinum-group metal.
Ruthenium in periodic context
Compare nearby or family-related elements without treating a trend as a substitute for element-specific evidence.
| Atomic number | 43 |
|---|---|
| Series | neighbor |
| Atomic number | 44 |
|---|---|
| Series | Group 8 |
| Atomic number | 45 |
|---|---|
| Series | neighbor |
Ruthenium 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 | 44 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 101.07 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Kr] 4d⁷ 5s¹ | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group 8 · Period 5 · d-block | Periodic-table placement | Evaluated |
| Electronegativity | 2.20 | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ¹⁰²Ru | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Shiny silvery platinum-group metal | Source-reviewed; see Sources below | Evaluated |
| Density | 12.1 g/cm³ | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | Hexagonal close-packed (HCP) | Ordinary ruthenium metal is HCP. The viewer is a conventional close-packed teaching cell and does not represent RuO₂, RuO₄ or coordination compounds. | Measured |
| Classification | Transition metal | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | Ordinary ruthenium metal is HCP. The viewer is a conventional close-packed teaching cell and does not represent RuO₂, RuO₄ or coordination compounds. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 2606 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 4420 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, ruthenium is treated as a solid below 2606 K, liquid between melting and approximately 4420 K, and gas above the boiling reference. The ordinary crystal label applies to the stated material reference; unmodeled solid allotropy is not fabricated. | 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 | +8, +6, +4, +3, +2, 0, −2 | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | Ru³⁺ | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Ruthenium sits in Group 8, Period 5 between technetium and rhodium, below iron and above osmium. Its partially filled 4d shell supports multiple oxidation states and rich coordination and catalytic chemistry. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ¹⁰²Ru | Most abundant natural isotope | One of several naturally occurring ruthenium isotopes. | Evaluated |
| ¹⁰¹Ru / ¹⁰⁴Ru | Natural isotopes | Useful reference isotopes in spectroscopy and nuclear science. | Evaluated |
| Natural ruthenium | Multi-isotope element | Isotope-specific properties must not be confused with the relative atomic mass. | Evaluated |
| Teaching nucleus | ¹⁰²Ru · 44 protons + 58 neutrons | Reference isotope used in the nucleus model | Reviewed |
Is Ruthenium a solid, liquid or gas? State at temperature
At approximately standard pressure, ruthenium is treated as a solid below 2606 K, liquid between melting and approximately 4420 K, and gas above the boiling reference. The ordinary crystal label applies to the stated material reference; unmodeled solid allotropy is not fabricated.
Where on Earth is Ruthenium found or produced?
Who discovered Ruthenium, and when?
Gottfried Osann proposed the name ruthenium while studying platinum residues, but his claimed new substances were not fully verified.
Karl Ernst Claus isolated, purified and confirmed ruthenium as a new element in Kazan and retained the name derived from Ruthenia.
Ruthenium chemistry expanded into hard alloys, electrical contacts and catalytic/electrochemical materials.
Ru is a low-abundance platinum-group element used mostly where a small amount provides high functional value.
From source material to Ruthenium applications: high-level material path
Ruthenium is obtained from mineral or metallurgical feedstocks in which it is chemically associated with other elements rather than mined as abundant native metal.
Industrial separation and refining produce element-specific compounds or metal feedstock; this guide does not provide operational extraction recipes.
The refined material is converted into the particular alloy, compound, doped host or component required by the application.
Recycling and recovery depend on the host product, concentration and economics; application materials must not be confused with pure element.
What is ruthenium used for?
Electronics
Ruthenium-containing resistor materials and contacts exploit stability, conductivity and wear resistance.
Catalysis
Ru complexes and supported catalysts are important in selected industrial and synthetic reactions.
Electrochemistry
Conductive RuO₂-containing coatings are used in selected anode technologies.
Alloys
Small Ru additions can harden platinum-group alloys.
Ruthenium isotopes and natural abundance
¹⁰²Ru
Most abundant natural isotopeOne of several naturally occurring ruthenium isotopes.
¹⁰¹Ru / ¹⁰⁴Ru
Natural isotopesUseful reference isotopes in spectroscopy and nuclear science.
Natural ruthenium
Multi-isotope elementIsotope-specific properties must not be confused with the relative atomic mass.
Five-question Ruthenium check
What is Ruthenium’s atomic number?
Which classification best fits Ruthenium?
What is the representative teaching isotope?
Which statement respects the material evidence?
Which rule should guide real-world uses?
Ruthenium 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 ruthenium?
Short answer: Ruthenium is chemical element 44, symbol Ru, a platinum-group transition metal.
Atomic number 44 means every ruthenium nucleus contains 44 protons. In the periodic table, Ruthenium is classified here as a transition metal in Period 5 and Group 8. Ruthenium sits in Group 8, Period 5 between technetium and rhodium, below iron and above osmium. Its partially filled 4d shell supports multiple oxidation states and rich coordination and catalytic chemistry.
Key point: Ru is element 44; its periodic position and electron structure explain the rest of the page.
What is ruthenium used for?
Short answer: Important uses include resistor materials, wear-resistant electrical contacts, catalysts and ruthenium-oxide electrochemical coatings.
Electronics: Ruthenium-containing resistor materials and contacts exploit stability, conductivity and wear resistance. Catalysis: Ru complexes and supported catalysts are important in selected industrial and synthetic reactions. Ruthenium metal, ruthenium oxide and “ruthenium red” are not the same material. Search results often mix the element with compounds and product names, so this guide keeps elemental Ru separate from RuO₂, RuO₄ and ruthenium-containing dyes or catalysts.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
Where is ruthenium found?
Short answer: It occurs with other platinum-group metals and can also be recovered from nickel/platinum-group processing streams.
Ruthenium is obtained from mineral or metallurgical feedstocks in which it is chemically associated with other elements rather than mined as abundant native metal. The Geography Explorer keeps natural occurrence separate from resources, industrial production and recycling, because those datasets answer different questions about ruthenium.
Key point: Natural occurrence, resources, production and recycling are different geography questions.
Who discovered ruthenium?
Short answer: Karl Ernst Claus confirmed and isolated ruthenium as a new element in the 1840s.
In 1820s, gottfried Osann proposed the name ruthenium while studying platinum residues, but his claimed new substances were not fully verified. In 1840s, karl Ernst Claus isolated, purified and confirmed ruthenium as a new element in Kazan and retained the name derived from Ruthenia.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
When was ruthenium discovered?
Short answer: The accepted discovery/confirmation belongs to the 1840s, after earlier unconfirmed claims.
In 1820s, gottfried Osann proposed the name ruthenium while studying platinum residues, but his claimed new substances were not fully verified. In 1840s, karl Ernst Claus isolated, purified and confirmed ruthenium as a new element in Kazan and retained the name derived from Ruthenia.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
What color is ruthenium?
Short answer: Elemental ruthenium is a shiny silvery metal.
The ordinary elemental-material description used here is: Shiny silvery platinum-group metal. Ruthenium metal, ruthenium oxide and “ruthenium red” are not the same material. Search results often mix the element with compounds and product names, so this guide keeps elemental Ru separate from RuO₂, RuO₄ and ruthenium-containing dyes or catalysts.
Key point: Elemental appearance can differ from the colors of its ions, compounds, oxide films or host materials.
How many valence electrons does ruthenium have?
Short answer: Transition-metal “valence electron” counts depend on context; the ground-state pattern is [Kr] 4d⁷ 5s¹, giving eight electrons beyond the krypton core.
The neutral-atom ground-state reference used on this page is [Kr] 4d⁷ 5s¹. 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 +8, +6, +4, +3, +2, 0, −2, 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.
Is ruthenium toxic?
Short answer: Hazard depends strongly on chemical form. Some ruthenium compounds are hazardous, so compound-specific safety data are required.
Ruthenium hazards are chemical-form specific. Do not generalize safety from elemental Ru to RuO₂, volatile RuO₄ or coordination compounds; consult material-specific safety information.
Key point: Safety claims must be substance- and exposure-specific.
Scientific sources for Ruthenium
- Royal Society of Chemistry - Ruthenium
- NIST - Atomic Weights and Isotopic Compositions
- IUPAC - Periodic Table of Elements
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