Ruthenium (Ru)

Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table.

Atomic Number

44

Atomic Mass

101.07 u

Category

transition metal

Phase

solid

Density

12.45 g/cm³

Electron Shells

2, 8, 18, 15, 1

Atomic Structure

Protons: 44 • Electrons: 44 • Neutrons: Varies by isotope

Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹ 4d⁷

Discovery

1844 • Karl Ernst Claus