All practice pages/Interatomic theory/Elements
Element 44, a transition metal
A hard platinum-group metal named for Russia, found in hard drives, electrical contacts and Nobel Prize-winning catalysts.
Period 5, group 8. The other transition metals are tinted, and every cell opens its own article.
Ruthenium has 44 electrons, one for every proton, so the atom carries no charge. Below are the same 44 electrons written two ways.
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d⁷ 5s¹
Short form: [Kr] 4d⁷ 5s¹, where [Kr] stands for the 36 electrons krypton already has.
That list runs by shell. In the order the subshells fill it reads [Kr] 5s¹ 4d⁷, because a subshell fills by its energy, not by its shell number.
The simple form counts electrons shell by shell. The orbital form says which subshell each one sits in: s holds 2, p holds 6, d holds 10 and f holds 14. Shell 3 here is 3s² 3p⁶ 3d¹⁰, and 2 + 6 + 10 is 18.
Ruthenium sits in period 5 and has 5 shells. The period number counts the shells.
The outer shell holds 1 electron. Those are the ones ruthenium can lose, gain or share, so they are the ones that decide what it bonds with.
Like other transition metals, ruthenium loses its outer s electrons, and often some d electrons as well, to form positive ions, and it can form more than one kind.
One of the rarest metals, found with platinum in ores from South Africa and Russia and recovered while refining platinum and nickel.
Karl Ernst Claus isolated it in 1844 at Kazan University from the residue left after dissolving platinum ore from the Ural Mountains, and named it after Ruthenia, a Latin name for Russia.
Thin ruthenium layers in hard disk drives, electrical contacts and chip resistors; a hardener in platinum and palladium jewelry; catalysts, including the Grubbs catalysts recognized by the 2005 Nobel Prize in Chemistry; and light-absorbing dyes for some solar cells.
Ruthenium tetroxide is volatile, toxic and can explode.