Bismuth
Element 83 · Post-Transition Metal
Bismuth is a brittle, silvery metal with a pinkish hue that grows stunning stair-step crystals with rainbow oxide colors when cooled slowly. It is the most diamagnetic of all metals and expands when it freezes, like water.
Medically it is a gentle giant: bismuth subsalicylate settles stomachs and fights the bacteria behind ulcers, with far lower toxicity than its neighbors lead and thallium. Industry uses it in low-melting alloys, cosmetics, and lead-free solders.
Key facts
| Atomic number | 83 |
|---|---|
| Atomic weight | 208.98 |
| Category | Post-Transition Metal |
| Group / Period | 15 / 6 |
| Block | p |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p3 |
| Common oxidation states | +3, +5 |
| State at STP | Solid |
| Electronegativity | 2.02 |
| Density | 9.78 g/cm³ |
| Melting point | 271.40 °C |
| Boiling point | 1564 °C |
Occurrence
Bismuth occurs as bismuthinite and as a byproduct of refining lead, copper, and tin ores. China is the dominant producer.
Applications
Stomach remedies (bismuth subsalicylate)
Cosmetics and pigments
Low-melting alloys and solders
Lead replacement in ammunition
Common compounds
- bismuth(III) oxide
- bismuth subsalicylate
- bismuth chloride
Bismuth is technically radioactive, but its half-life is over a billion times longer than the age of the universe — so it counts as stable for every practical purpose.
Data source: IUPAC standard atomic weights 2021