Return to the Main CHEMystery Page.
Return to the Periodic Table of the Elements

Element 44 - Ruthenium (Ru) sound

From Ruthenia, Latin for Russia; discovered 1844. Pure ruthenium is too hard and brittle to machine. It makes a top-notch "hardener," however, when it is alloyed with platinum. But used in excess of 15 percent, ruthenium is ruinous, making the metals too hard to be worked.

Properties

Atomic Number: 44
Atomic Weight: 101.07
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d75s1
Oxidation States (Bold most stable): +2, +3, +4, +6, +8
Boiling Point (K): 4425
Melting Point (K): 2610
Density (at 300K -- g/cm3): 12.37
Atomic Volume (at 300K -- cm3/mol) 8.30
Number of stable isotopes: 7
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 106 -- 267 days -- beta particle (electron) emission
Covalent Radius (Å): 1.25
Atomic Radius (Å): 1.34
First Ionization Potential (V): 7.37
Electronegativity (Pauling's): 2.2
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.238
Heat of Vaporization (kJ/mol): 567.77
Heat of Fusion (kJ/mol): 25.52
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 14.9
Thermal Conductivity (at 300K -- W m-1 K-1): 117
Crystal Structure: Hexagonal
Acid-Base Properties: Slightly acidic