Bismuth (Bi)
Bismuth is element 83, a post-transition metal in group 15, period 6. A neutral atom has 83 protons, 126 neutrons and 83 electrons, 5 of them valence electrons.
Post-transition metal- Atomic number
- 83
- Atomic mass
- 208.98 u
- Valence electrons
- 5
- Protons · neutrons
- 83 · 126
- Electrons per shell
- 2, 8, 18, 32, 18, 5
- At room temperature
- solid
Bohr model of bismuth
The Bohr model draws bismuth as a nucleus of 83 protons and 126 neutrons, with its 83 electrons on 6 circular shells: 2 in shell 1, 8 in shell 2, 18 in shell 3, 32 in shell 4, 18 in shell 5, 5 in shell 6. Press Build the atom to watch the shells fill from the inside out. The outer ring (the P 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 bismuth
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p³
Short form (noble gas notation): [Xe] 6s² 4f¹⁴ 5d¹⁰ 6p³. The [Xe] stands for the electrons of xenon, the noble gas before it.
How many valence electrons does bismuth have?
Bismuth has 5 valence electrons.
Bismuth is in group 15, and for groups 13–18 you subtract 10 from the group number: 15 − 10 = 5. It tends to share electrons in covalent bonds.
Protons, neutrons and electrons
| Protons | 83 | equal to the atomic number |
|---|---|---|
| Electrons | 83 | equal to the protons in a neutral atom |
| Neutrons | 126 | mass number 209 − 83 protons |
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.
Bismuth properties
| Symbol | Bi |
|---|---|
| Category | Post-transition metal |
| Group · period · block | 15 · 6 · p |
| Atomic mass | 208.98 u |
| State at 25 °C | solid |
| Melting point | 544.5 K (271 °C, 521 °F) |
| Boiling point | 1,837 K (1,560 °C, 2,850 °F) |
| Density | 9.807 g/cm³ |
| Electronegativity (Pauling) | 2.02 |
| Atomic radius | 207 pm |
| First ionization energy | 7.289 eV |
| Electron affinity | 0.946 eV |
| Oxidation states | +5, +3 |
| Common ion charge | +5, +3 |
| Discovered | 1753 by Claude François Geoffroy |
Where bismuth sits on the periodic table
Group 15: Nitrogen, Phosphorus, Arsenic, Antimony, Moscovium.
Questions about bismuth
How many valence electrons does bismuth have?
Bismuth has 5 valence electrons.
How many protons, neutrons and electrons does bismuth have?
A neutral bismuth atom has 83 protons and 83 electrons. Its most common form has about 126 neutrons (mass number 209 − 83 protons).
What is the electron configuration of bismuth?
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p³, written in short form as [Xe] 6s² 4f¹⁴ 5d¹⁰ 6p³.
What does the Bohr model of bismuth look like?
A nucleus of 83 protons and 126 neutrons, circled by 6 electron shells holding 2, 8, 18, 32, 18, 5 electrons.
What is the atomic number of bismuth?
83. The atomic number is the number of protons in the nucleus, and it is what makes an atom bismuth.