Name: ruthenium
Symbol: Ru
Atomic number: 44
Atomic weight: 101.07 (2) g
Group in periodic table: 8
Group name: Precious metal
Period in periodic table: 5
Block in periodic table: d-block
CAS registry ID: 7440-18-8
Ruthenium is a hard, white metal. It does not tarnish at room temperatures, but oxidises in air at about 800°C. The metal is not attacked by hot or cold acids or aqua regia, but when potassium chlorate is added to the solution, it oxidises explosively.