Rutherfordium (Rf)
Rutherfordium is element 104, a transition metal in group 4, period 7. A neutral atom has 104 protons, 163 neutrons and 104 electrons, 2 of them valence electrons.
Transition metal- Atomic number
- 104
- Atomic mass
- [267] u
- Valence electrons
- 2*
- Protons · neutrons
- 104 · 163
- Electrons per shell
- 2, 8, 18, 32, 32, 10, 2
- At room temperature
- —
Bohr model of rutherfordium
The Bohr model draws rutherfordium as a nucleus of 104 protons and 163 neutrons, with its 104 electrons on 7 circular shells: 2 in shell 1, 8 in shell 2, 18 in shell 3, 32 in shell 4, 32 in shell 5, 10 in shell 6, 2 in shell 7. Press Build the atom to watch the shells fill from the inside out. The outer ring (the Q shell) is dashed: the electrons there are the ones that take part in chemistry.
Real electrons don't travel in neat circles. They live in fuzzy orbitals, shown below, but the Bohr picture is the quickest way to count shells and valence electrons.
Electron configuration of rutherfordium
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d²
Short form (noble gas notation): [Rn] 7s² 5f¹⁴ 6d². The [Rn] stands for the electrons of radon, the noble gas before it.
How many valence electrons does rutherfordium have?
Rutherfordium has 2 valence electrons.
Rutherfordium is a transition metal, so its valence electrons are less clear-cut than for main-group elements. It has 2 electrons in its outermost shell (shell 7), and electrons in its inner d subshell can also take part in bonding.
Protons, neutrons and electrons
| Protons | 104 | equal to the atomic number |
|---|---|---|
| Electrons | 104 | equal to the protons in a neutral atom |
| Neutrons | 163 | mass number 267 − 104 protons (for its longest-lived isotope, Rf-267) |
Atoms of the same element can have different numbers of neutrons (isotopes). The count above uses the rounded atomic mass, the way it's taught in class.
Rutherfordium properties
| Symbol | Rf |
|---|---|
| Category | Transition metal |
| Group · period · block | 4 · 7 · d |
| Atomic mass | [267] u |
| State at 25 °C | solid |
| Melting point | — |
| Boiling point | — |
| Density | — |
| Electronegativity (Pauling) | — |
| Atomic radius | — |
| First ionization energy | — |
| Electron affinity | — |
| Oxidation states | +4 |
| Common ion charge | +4 |
| Discovered | 1964 by Joint Institute for Nuclear Research |
Where rutherfordium sits on the periodic table
Group 4: Titanium, Zirconium, Hafnium.
Questions about rutherfordium
How many valence electrons does rutherfordium have?
Rutherfordium has 2 valence electrons in its outer shell; inner d or f electrons can also bond.
How many protons, neutrons and electrons does rutherfordium have?
A neutral rutherfordium atom has 104 protons and 104 electrons. Its most common form has about 163 neutrons (mass number 267 − 104 protons).
What is the electron configuration of rutherfordium?
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴ 6d², written in short form as [Rn] 7s² 5f¹⁴ 6d².
What does the Bohr model of rutherfordium look like?
A nucleus of 104 protons and 163 neutrons, circled by 7 electron shells holding 2, 8, 18, 32, 32, 10, 2 electrons.
What is the atomic number of rutherfordium?
104. The atomic number is the number of protons in the nucleus, and it is what makes an atom rutherfordium.