Rhodium
A rare, reflective metal vital to catalytic converters.
Inside the Rhodium atom
Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Rhodium atom step by step.
Electron configuration
[Kr] 4d8 5s1
A neutral Rhodium atom has 45 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.
Shell distribution
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Physical & atomic properties
- State (room temp)
- Solid
- Melting point
- 2237 K (1964 °C)
- Boiling point
- 3968 K (3695 °C)
- Density
- 12.41 g/cm³
- Electronegativity
- 2.28 Pauling
- Atomic radius
- 135 pm
- 1st ionization energy
- 720 kJ/mol
- Category
- Transition metals
Discovery & naming
- Discovered
- 1803
- Discovered by
- William Hyde Wollaston
- Origin of name
- Greek 'rhodon', meaning rose.
Notable uses
Catalytic converters, jewellery, and reflective coatings.
Where Rhodium comes from
Neutron star mergers
Dominated by rapid neutron capture, so it is associated with violent, neutron-rich events.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 45
- Atomic mass
- 102.91
- Category
- Transition metals
- Group · Period
- 9 · 5
- Block
- d-block
- Shells
- 2 · 8 · 18 · 16 · 1