Ruthenium
Definition and meaning of Ruthenium in chemistry.
Ruthenium is a rare, hard, silvery-white transition metal of the platinum group, denoted by the chemical symbol Ru and an atomic number of 44. It is exceptionally resistant to wear and remains unreactive to most chemicals, making it a highly durable and versatile precious metal.
In more detail
Occupying group 8 and period 5 of the periodic table, ruthenium is generally found in complex ores alongside other platinum group metals in regions such as the Ural Mountains and specialized deposits in North and South America. As a classical noble metal, it does not tarnish at room temperatures and is entirely unaffected by most acids, including boiling aqua regia, but can be aggressively attacked by halogens or oxidized by strong alkaline melts. The element can exist in multiple diverse oxidation states, typically +2, +3, and +4, and uniquely forms complex coordination compounds with rich catalytic properties used in olefin metathesis. It is highly notable for its metallurgical ability to significantly harden platinum and palladium alloys, and to dramatically improve the comprehensive corrosion resistance of titanium when added in microscopic amounts. Ruthenium compounds are continuously researched for their photophysical properties in solar energy conversion technologies and evaluated as deeply promising alternatives to platinum-based anticancer therapeutics.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Ru |
| Atomic number | 44 |
| Atomic mass | 101.07 u |
| Category | Transition Metal |
| State at room temperature | Solid |
| Melting point | 2334 °C |
| Boiling point | 4150 °C |
| Year discovered | 1844 |
Ruthenium is frequently used to coat the highly specialized anodes of electrochemical cells for large-scale chlorine production and serves as an important catalyst for breaking down hydrogen sulfide in industrial processes.
Frequently asked questions
Is ruthenium toxic?
While metallic ruthenium is largely inert and biologically non-toxic, some of its compounds, particularly the highly volatile ruthenium tetroxide (RuO4), are exceptionally toxic and dangerous.
What makes ruthenium useful in electronics?
Its excellent wear resistance and stable electrical conductivity make it absolutely ideal for use in high-performance wear-resistant electrical contacts and precision thick-film resistors.