More attractive metals, like tin, were thought to be partially grown. The most mature metals were silver and gold. This made identification very difficult. Were chemists looking at "older lead" or a "younger tin? Bismuth is one of the elements often confused with other elements. Old manuscripts show that bismuth was often confused with lead, tin, antimony, or even silver. Bismuth was used in early alloys.
An alloy is made by melting and mixing two or more metals. The mixture has properties different from those of the individual metals. The first printing presses dating back to the s held type made of bismuth alloys. As with arsenic and antimony, it is difficult to say who exactly discovered bismuth.
The name bismuth was probably taken from two German words, weisse masse, meaning "white mass. Later the name was shortened to wismuth, and then to bisemutum, before bismuth came into common use. Bismuth is a soft, silvery metal with a bright, shiny surface and a yellowish or pinkish tinge. The metal breaks easily and cannot be fabricated worked with at room temperature.
Its density is 9. Bismuth expands as it solidifies changes from a liquid to a solid. Most materials contract have a smaller volume as they solidify. Few elements behave like bismuth. This property makes bismuth useful for producing type metal. An alloy of bismuth is melted and poured into molds that have the shape of letters and numbers.
As the type cools, it solidifies and expands to fill all the comers of the mold. The type formed is clear, crisp, and easy to read. Computer typesetting, however, has largely replaced bismuth metal typesetting. Bismuth combines slowly with oxygen at room temperature.
Bismuth oxide Bi 2 O 3 gives the metal its pinkish or yellowish tinge. At higher temperatures, the metal burns to form bismuth oxide. Bismuth also reacts with most acids. The abundance of bismuth in the Earth's crust is estimated to be about 0. This puts it in the bottom quarter of the elements according to their abundance in the earth. Bismuth is seldom found in its elemental state as a pure metal in the earth.
Its compounds are generally found along with ores of other metals, such as lead, silver, gold, and cobalt. The most important mineral of bismuth is bismuthinite, also known as bismuth glance Bi 2 S 3. Bismuth is produced in the United States only as a by-product of lead refining in Nebraska.
There is only one naturally occurring isotope of bismuth, bismuth Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element's name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary.
Each variation is an isotope. A number of radioactive isotopes of bismuth are known also. A radioactive isotope is one that breaks apart and gives off some form of radiation. Radioactive isotopes are produced when very small particles are fired at atoms.
These particles stick in the atoms and make them radioactive. Bismuth metal is usually separated from ores of other metals by the Betterton-Kroll process. Calcium or magnesium is added to the molten melted ore where it forms an alloy with bismuth.
Later, the bismuth can be separated from the calcium or magnesium to make the pure metal. It is stated that the administration of bismuth should be stopped when gingivitis appears, for otherwise serious ulceration stomatitis is likely to result. Other toxic results may develop, such as vague feeling of bodily discomfort, presence of albumin or other protein substance in the urine, diarrhea, skin reactions and sometimes serious exodermatitis.
May be a nuisance dust causing respiratory irritation. May cause foul breath, metallic taste and gingivitis. May cause nausea, loss of appetite and weight, malaise, albuminuria, diarrhea, skin reactions, stomatitis, headache, fever, sleeplessness, depression, rheumatic pain and a black line may form on gums in the mouth due to deposition of bismuth sulphide.
Skin: May cause irritation. Eyes: May cause irritation. Ingestion: May affect the function of the liver and the kidneys. May cause anemia, black line may form on gums and ulcerative stomatitis. Skin: May cause dermatitis. Eyes: No chronic health effects recorded. Medical conditions generally aggravated by the exposure: Pre-existing skin and respiratory disorders. Bismuth metal is not considered toxic and poses minimum threat to the environment.
Bismuth compounds generally have very low solubility but they should be handled with care, as there is only limited information on their effects and fate in the environment. Back to chart periodic elements. Toggle navigation. Home Periodic table Elements Bismuth. About Lenntech. General Delivery Conditions. Privacy Policy. All rights reserved. Atomic number. Bismuth Bismuth is a white, crystalline, brittle metal with a pinkish tinge.
Applications Bismuth metal is used in the manufacture of low melting solders and fusible alloys as well as low toxicity bird shot and fishing sinkers.
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