Ruthenium
Definition and meaning of Ruthenium in chemistry.
![Ruthenium element card: symbol Ru, atomic number 44, atomic mass 101.07, electron configuration [Kr] 4d⁷ 5s¹, oxidation states +4 +3, Transition metal, group 8, period 5, solid at room temperature.](/assets/images/terms/ruthenium-chemical-element.webp)
Ruthenium is a rare, hard, silvery-white transition metal in the platinum group. It uses the symbol Ru and atomic number 44 on the periodic table. It resists wear and most chemicals, making it a highly durable precious metal.
In more detail
Ruthenium sits in group 8 and period 5 of the periodic table of elements. Miners find it in complex ores with other platinum group metals in the Ural Mountains. It is classified as a classic noble metal because it resists corrosion in moist air.
Ruthenium does not tarnish at normal room temperatures and remains unaffected by most strong acids. This incredible resistance includes boiling aqua regia, which is a very strong acid mixture. However, it can be aggressively attacked by halogens or oxidized by strong alkaline melts.
Halogens are highly reactive nonmetal elements like chlorine, fluorine, and bromine. Ruthenium can exist in several different oxidation states, but +2, +3, and +4 are most common. It forms complex coordination compounds with other molecules to offer rich catalytic properties.
A catalyst is a unique substance that significantly speeds up a chemical reaction. Ruthenium catalysts help drive important olefin metathesis reactions in organic chemistry laboratories. The element is famous for hardening platinum and palladium alloys for industrial use.
An alloy is a solid, durable mixture composed of two or more distinct metals. Adding a microscopic amount of ruthenium greatly improves the corrosion resistance of titanium. Researchers study ruthenium compounds for use in new solar energy conversion technologies. They are also testing these compounds as promising alternatives to platinum-based cancer drugs.
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 |
| Year discovered | 1844 |
Ruthenium is frequently used to coat the anodes of large electrochemical cells. An anode is the positive electrode utilized within a standard electrical circuit. These specially coated cells help produce chlorine gas on a massive industrial scale. Ruthenium also acts as a vital catalyst to break down toxic hydrogen sulfide.
Frequently asked questions
Is ruthenium toxic?
Metallic ruthenium is largely inert and generally safe for humans to handle. However, some of its compounds are extremely dangerous and toxic. For example, ruthenium tetroxide (RuO4) is a highly toxic and volatile chemical compound.
What makes ruthenium useful in electronics?
The metal possesses excellent wear resistance and highly stable electrical conductivity. These vital traits make it absolutely perfect for high-performance electrical contacts. Manufacturers also use it to create precision thick-film resistors.
Related terms
Sources & references
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