Element 44
Ruthenium
Transition metals
Ruthenium (Ru) is in the d-block of the periodic table — group 8, period 5.
Ruthenium is a chemical element with symbol Ru and atomic number 44.
Key data
- Atomic number
- 44
- Atomic mass
- 101.072 u
- Group / Period
- 8 / 5
- Block
- d-block
- Phase at STP
- Solid
- Density
- 12.45 g/cm³
- Melting point
- 2333.8 °C
- Boiling point
- 4149.9 °C
- Electron configuration
- [Kr] 4d7 5s1
Periodic table block
Ruthenium is in the d-block (group 8, period 5). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Hard-disk coatings
- •Solar cells
- •Catalysts
Discovery
Year: 1844
Discovered by: Karl Ernst Claus
Frequently asked questions
What is the atomic number of Ruthenium?
Ruthenium has atomic number 44. Its symbol is Ru and its atomic mass is 101.072 u.
What category of element is Ruthenium?
Ruthenium is classified as transition metals. It sits in group 8, period 5 of the periodic table.
What block of the periodic table is Ruthenium in?
Ruthenium is in the d-block (group 8, period 5). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Kr] 4d7 5s1.
What is Ruthenium used for?
Common uses of Ruthenium include: Hard-disk coatings, Solar cells, Catalysts.
When was Ruthenium discovered?
Ruthenium was discovered in 1844 by Karl Ernst Claus.
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