RUTHENIUM

TRANSITION ELEMENT: IRON GROUP

Atomic number:	44
Group numbers:	8
Period:	5
Electronic configuration:	[Kr] 4d⁷ 5s¹
Formal oxidation number:	+3
Electronegativities:	2.2
Atomic radius / pm:	132.5
Relative atomic mass:	101.07(2)

Ruthenium was discovered by Karl Karlovich Klaus (RU) in 1844. The origin of the name comes from the Latin word Ruthenia meaning Russia. It is a rare, extremely brittle, silver-grey metal. Ruthenium is unaffected by air, water or acids but reacts with very hot (molten) alkalis. Ruthenium is found in pentlandite and pyroxinite. It is used to harden platinum and palladium, aircraft magnetos use platinum alloy with 10% ruthenium. The price of 99.95 % pure ruthenium sponge is 784.80 € for 50 g.

PHYSICAL PROPERTIES
Density / g dm^-3:	12370	(293 K)
	10900	(m.p.)
Molar volume / cm³mol^-1:	8.17	(293 K)
	9.27	(m.p.)
Electrical resistivity / µΩcm:	7.6	(20 °C)

THERMAL PROPERTIES
Thermal conductivity / W m^-1K^-1:	117
Melting point / °C:	2334
Boiling point / °C:	4150
Heat of fusion / kJ mol^-1:	23.7
Heat of vaporization / kJ mol^-1:	567
Heat of atomization / kJ mol^-1:	641.031

IONIZATION ENERGIES
First ionization energy / kJ mol^-1:	710.19
Second ionization energy / kJ mol^-1:	1617.11
Third ionization energy / kJ mol^-1:	2746.96

ABUNDANCE OF ELEMENT
in the atmosphere / ppm:	-
in the Earth's crust / ppm:	0.01
in the oceans / ppm:	-

CRYSTALLOGRAPHIC DATA
Crystal structure:	hexagonal
Unit-cell dimensions / pm:	a=270.58, c=428.11
Space group:	P6₃/mmc

ISOTOPES
Isotope	Relative atomic mass	Mass percent (%)
⁹⁶Ru	95.907598(8)	5.52(6)
⁹⁸Ru	97.905287(7)	1.88(6)
⁹⁹Ru	98.905939(2)	12.7(1)
¹⁰⁰Ru	99.904220(2)	12.6(1)
¹⁰¹Ru	100.905582(2)	17.0(1)
¹⁰²Ru	101.904350(2)	31.6(2)
¹⁰⁴Ru	103.905430(4)	18.7(2)

REDUCTION POTENTIALS
Balanced half-reaction	E^o / V
Ru²⁺ + 2e^- → Ru(s)	+0.45
RuO₂(s) + 4H⁺ + 4e^- → Ru(s) + 2H₂O	+0.79
RuO₄(s) + e^- → RuO₄^-	+1.00
RuO₄^- + e^- → RuO₄^2-	+0.59
RuCl₅^- + 2e^- → Ru²⁺ + 5Cl^-	+0.3
RuCl₃ + 3e^- → Ru(s) + 3Cl^-	+0.68

43 Technetium

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44 Ruthenium

→

45 Rhodium

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Citing this page:

Generalic, Eni. "Ruthenium." EniG. Periodic Table of the Elements. KTF-Split, 18 Jan. 2024. Web. {Date of access}. <https://www.periodni.com/ru.html>.