Bismuth
Definition and meaning of Bismuth in chemistry.
![Bismuth element card: symbol Bi, atomic number 83, atomic mass 208.98, electron configuration [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³, oxidation states +3, Post-transition metal, group 15, period 6, solid at room temperature.](/assets/images/terms/bismuth-chemical-element.webp)
Bismuth is a brittle, crystalline, white post-transition metal with a distinct pinkish tinge. It has the chemical symbol Bi and the atomic number 83. It strongly repels magnetic fields and conducts heat very poorly.
In more detail
Bismuth sits in group 15 of the periodic table immediately after lead. It shares many chemical properties with its neighbors arsenic and antimony. You can find bismuth in nature as a pure elemental metal.
Miners also extract it from common ores like bismuthinite and bismite. Companies usually produce bismuth as a byproduct of other mining operations. They collect it while extracting lead, copper, tin, silver, and gold.
Bismuth has a very unusual physical property during phase changes. Liquid bismuth expands slightly as it freezes into a solid state. Water is one of the few other substances that expands upon freezing.
Bismuth is the most diamagnetic of all naturally occurring metals. A diamagnetic material weakly repels an externally applied magnetic field. Bismuth also has an extremely low thermal conductivity.
This means it does not transfer heat well across its surface. Chemists consider bismuth to be an exceptionally stable chemical element. Its only natural isotope is bismuth-209.
Scientists consider bismuth-209 technically radioactive. However, this isotope decays incredibly slowly over time. Its half-life is vastly longer than the estimated age of the universe.
Bismuth has very low toxicity to biological life forms. Heavy metals like lead are very poisonous to human health. Manufacturers frequently use bismuth as a safer replacement for lead. It provides high density and mass without the severe health risks.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Bi |
| Atomic number | 83 |
| Atomic mass | 208.98 u |
| Category | Post-Transition-Metal |
| Melting point | 271.5 °C (520.7 °F) |
Bismuth subsalicylate is an active chemical ingredient in many popular medicines. People buy these over-the-counter remedies to soothe common stomach problems. The chemical helps treat everyday human ailments like indigestion and heartburn. It also relieves nausea and cures diarrhea safely and effectively.
Frequently asked questions
Why do manufacturers use bismuth to replace lead?
Bismuth shares many physical properties with lead. It has a high density and a low melting point. Unlike lead, bismuth does not poison the human nervous system.
Is bismuth a completely stable element?
No, natural bismuth-209 is weakly radioactive. It slowly decays by releasing an alpha particle. Its half-life is about 1.9 x 10^19 years.
Related terms
Sources & references
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