Bismuth is a chemical element with the symbol Bi and atomic number 83. Elemental bismuth may occur naturally, although its sulfide and oxide form important commercial ores. The free element is 86% as dense as lead. It is a brittle metal with a silvery-white color when freshly produced, but surface oxidation can give it an iridescent tinge in numerous colours. Bismuth is the most naturally diamagnetic element and has one of the lowest values of thermal conductivity among metals.
Cool facts about Bismuth
- When liquid bismuth freezes, it expands rather than contracts because it forms a crystalline structure similar to water. Four other metals expand when they freeze: silicon, gallium, antimony and germanium.
- Bismuth subsalicylate (C7H5BiO4), sold under the brand names Pepto-Bismol and Kaopectate, is a well-known remedy for stomach aches and diarrhea. It works by decreasing the flow of fluids and electrolytes into the bowel, reduces inflammation within the intestine, and may kill the organisms that can cause diarrhea.
- Bismuth Trioxide is a key ingredient a popular firework effect known as the “Dragon’s Egg” and is also used in firework “sparklers.”
- In ancient Egypt, a bismuth compound named bismoclite was used for cosmetic purposes.
- Of all metal elements, bismuth has the highest electrical resistance, the lowest thermo-conductivity (except mercury), and the highest Hall Effect (increase in electrical resistance when placed in a magnetic field). No other element has a higher level of diamagnetism than Bismuth. Diamagnetism is the ability for an object to create its own magnetic field opposing the magnetic field of another source.
- Bismuth ranks 65th in elemental abundance in the Earth’s crust, at an estimated 85 parts per billion by weight, constituting much less than 0.001% of the total. Bismuth abundance in our solar system is 10 parts per billion by weight.