Bismuth

Bismuth
Properties
Atomic symbol	Bi
Atomic number	83
Classification	Pnictogen
Atomic mass	208.9804 amu
Number of Stable Isotopes	1
Density (grams per cc)	9.8 g/cm^3
Other Information
Date of discovery	Known since the 15th century.
Name of discoverer	Shown to be a distinct element in 1753 by Claude Geoffrey
Name origin	From the German bisemutum, related to wissmuth, "white mass".
Uses	Pharmaceuticals, alloys, electronics, pigments, fire alarms, and pyrotechnics
Obtained from	Bismuthine, bismuthinite, bismite, bismutite. Commercially obtained as byproduct of lead or copper smelting.

Bismuth is an element that has the symbol Bi and atomic number 83. It is in the "pnictogen" (phosphorus group) column of the periodic table.

This heavy, brittle, white crystalline trivalent metal has a pink tinge and chemically resembles arsenic and antimony. Of all the metals, it is the most naturally diamagnetic, and only mercury has a lower thermal conductivity. It has generally been considered to be the last stable, non-radioactive element on the periodic table. But its one "stable" isotope was recently shown to be radioactive with half-life of over 10¹⁹ (19 quintillion) years.

Bismuth compounds are used in cosmetics, medicines, and in medical procedures. As the toxicity of lead has become more apparent in recent years, alloy uses for bismuth metal as a replacement for lead have become an increasing part of bismuth's commercial importance.

Alloys with bismuth can have very low melting points, and are used as triggers in fire sprinkler systems.