44
Ru
Ruthenium
101.07
Ruthenium (Ru)
Transition MetalGroup 8Period 5d-block-block
Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals.
Latin name: Ruthenium
Atomic Number
44
Atomic Mass
101.07 g/mol
Phase (STP)
Solid
Electron Config.
[Kr] 4d⁷ 5s¹
General
SymbolRu
Atomic Number44
Atomic Mass101.07 g/mol
CategoryTransition Metal
Group8
Period5
Blockd-block
Electron Configuration[Kr] 4d⁷ 5s¹
Valence Electrons8
Coloursilvery-white metallic
Appearancesilvery white metallic
CAS NumberCAS7440-18-8
Physical Properties
Phase (STP)Solid
Density12.45 g/cm³
Melting Point2333.85°C · 4232.93°F · 2607.00 K
Boiling Point4149.85°C · 7501.73°F · 4423.00 K
Atomic Properties
Atomic Radius178 pm
Electronegativity2.2 Pauling
Ionization Energy710 kJ/mol
Oxidation States+8, +6, +4, +3, +2, 0
Ion ChargeRu3+/Ru4+/Ru8+
Thermodynamic
Molar Heat24.06 J/(mol·K)
Crystal Structure
Crystal Structurehexagonal close-packed
Mechanical Properties
Mohs Hardness6.5
Abundance
In Universe0.00001%
In Sun0.000009%
In Earth's Crust0.00001%
In Oceans0.0000002%
In Meteorites0.00001%
Discovery & History
Discovery Year1844
Discovered ByKarl Ernst Claus
Country of DiscoveryRussia
Isotopes of Ruthenium
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Ru-96 | 5.54% | Stable | — |
| Ru-98 | 1.87% | Stable | — |
| Ru-99 | 12.76% | Stable | — |
| Ru-100 | 12.6% | Stable | — |
| Ru-101 | 17.06% | Stable | — |
| Ru-102 | 31.55% | Stable | — |
| Ru-104 | 18.62% | Stable | — |