ElementsWhat is bismuth?
Bismuth is a brittle, silvery metal with a pink tinge. Its crystals form stepped shapes with rainbow colours. It is one of the least poisonous heavy metals.
What is bismuth used for?
Stomach medicines, low-melting alloys for fire sprinklers, and a replacement for lead in solders and shot.
Where the name comes from
Probably from old German words meaning 'white mass'.
Key facts
- Symbol
- Bi
- Atomic number
- 83
- Atomic mass
- 208.98040 u
- Family
- Post-transition metal
- Period
- 6
- Group
- 15
- Block
- p
- State at room temperature
- Solid
- Melting point
- 271.4 °C (544.55 K, 521 °F)
- Boiling point
- 1,564 °C (1,837 K, 2,847 °F)
- Density
- 9.81 g/cm³
- Electrons per shell
- 2, 8, 18, 32, 18, 5
- Electron configuration
- [Xe]6s2 4f14 5d10 6p3
- Common oxidation states
- +5, +3
- Electronegativity (Pauling)
- 2.02
- First ionisation energy
- 7.289 eV
- Electron affinity
- 0.946 eV
- Atomic radius (van der Waals)
- 207 pm
- Discovered
- 1753
Place in the periodic table
Bismuth is element number 83. It sits in period 6 (row 6) of the periodic table, in group 15 (column 15), and belongs to the p-block. Just before it comes lead (82), and just after it comes polonium (84). In the same column, antimony is above it and moscovium is below it. Elements in one column tend to behave alike.
Family: Post-transition metals.
Physical properties
At room temperature bismuth is a solid. It melts at 271.4 °C and boils at 1,564 °C, so it stays liquid over a range of 1,292 degrees. Its density is 9.81 grams per cubic centimetre, so a one-litre block would weigh about 9.81 kilograms. By density it ranks 28th among the 96 elements with a measured value.
Inside the atom
An atom of bismuth has 83 protons in its nucleus and, when neutral, 83 electrons around it. The electrons are arranged in 6 shells: 2, 8, 18, 32, 18, 5. The outermost shell holds 5 electrons. Written in full, the electron configuration is [Xe]6s2 4f14 5d10 6p3.
Its electronegativity on the Pauling scale is 2.02. This number shows how strongly an atom pulls shared electrons towards itself: fluorine, the strongest, is 3.98. Removing one electron from an atom takes 7.289 electronvolts (about 703 kilojoules per mole). One mole of bismuth weighs 208.98040 grams, so a single gram contains about 2.88 × 1021 atoms.
The ring picture is a simple model that only counts the electrons in each shell. Real atoms do not look like this.
Next steps
- Work out the weight of a compound that contains bismuth with the molar mass calculator.
- Compare it with every other element in the sortable list.
- Test yourself with the symbol quiz.
Figures on this page are from PubChem (U.S. National Library of Medicine), as downloaded on 11 November 2026. See About and data sources.