Element 104 · Transition metal
Rutherfordium (Rf) — Element 104
Ernest Rutherford
Rutherfordium (Rf) is a transition metal in Period 7, Group 4 of the periodic table with atomic number 104, standard atomic weight [267] u, and ground-state electron configuration [Rn] 5f¹⁴ 6d² 7s². At standard temperature and pressure it is classified as a short-lived synthetic nuclide with 4 valence electrons and common oxidation states +4.
Research only
What are the atomic properties and physical constants of Rutherfordium?
Reference constants compiled from IUPAC standard atomic weights, the NIST Atomic Spectra Database, and the CRC Handbook.
- Atomic number (Z)
- 104
- Standard atomic mass
- [267] u
- Chemical family
- Transition metal
- Ground-state configuration
- [Rn] 5f¹⁴ 6d² 7s²
- Electrons per shell
- 2, 8, 18, 32, 32, 10, 2
- Valence electrons
- 4
- Common ion charges / oxidation states
- +4
- Phase at STP
- Synthetic
- Pauling electronegativity
- —
- First ionization energy
- —
- Atomic radius
- —
- Melting point
- —
- Boiling point
- —
- Discovery year
- 1969
- Table coordinate
- Period 7, Group 4
- Radioactivity
- Radioactive (no stable isotopes)
How are electrons arranged across Rutherfordium’s shells?
A neutral Rutherfordium atom contains 104 electrons distributed across 7 occupied principal energy shells ([Rn] 5f¹⁴ 6d² 7s²). The table below compares Rutherfordium’s shell occupancy against each shell’s theoretical 2n² capacity.
| Principal Shell (n) | Spectroscopic Letter | Electrons in Rf | Max Shell Capacity (2n²) |
|---|---|---|---|
| n = 1 | K | 2 e⁻ | 2 e⁻ |
| n = 2 | L | 8 e⁻ | 8 e⁻ |
| n = 3 | M | 18 e⁻ | 18 e⁻ |
| n = 4 | N | 32 e⁻ | 32 e⁻ |
| n = 5 | O | 32 e⁻ | 50 e⁻ |
| n = 6 | P | 10 e⁻ | 72 e⁻ |
| n = 7 | Q | 2 e⁻ | 98 e⁻ |
Frequently Asked Questions about Rutherfordium (Rf)
What is the atomic mass and atomic number of Rutherfordium (Rf)?
Rutherfordium (Rf) has atomic number Z = 104 (104 protons in its nucleus) and an IUPAC standard atomic weight of [267] u. It sits in Period 7, Group 4 and is classified as a transition metal.
What is the ground-state electron configuration of Rutherfordium?
The neutral ground-state electron configuration of Rutherfordium (Z = 104) is [Rn] 5f¹⁴ 6d² 7s². Across its 7 occupied principal shells (n = 1 to n = 7), the electrons per shell are 2, 8, 18, 32, 32, 10, 2, with 4 valence electrons participating in bonding.
What are the common ion charges and electronegativity of Rutherfordium?
Rutherfordium commonly forms +4 oxidation states or ion charges in compounds. Its Pauling electronegativity is — and its first ionization energy is —.
When was Rutherfordium discovered and what is it used for?
Rutherfordium was discovered in 1969 (Ernest Rutherford). Research only
How does Rutherfordium compare to neighboring elements?
Other transition metal elements: