A metalloid is a chemical element that has properties in between those of metals and nonmetals. There is no standard definition of a metalloid, nor is there agreement as to which elements are appropriately classified as such. Despite this uncertainty, the term remains in use in chemistry literature. The six commonly recognised metalloids are boron, silicon, germanium (pictured), arsenic, antimony and tellurium. Elements less commonly recognised as metalloids include carbon, aluminium, selenium, polonium and astatine. Typical metalloids have a metallic appearance but are brittle and only fair conductors of electricity. Chemically, they mostly behave as weak nonmetals. They can form alloys with metals. Most of their other properties are intermediate in nature. Metalloids and their compounds are used in alloys, biological agents, flame retardants, glasses, optical storage and optoelectronics, pyrotechnics, semiconductors and electronics. The term metalloid originally referred to nonmetals. Its more recent meaning, as a category of elements with intermediate properties, became widespread in 1940–1960. Metalloids are sometimes called semimetals, a practice that has been discouraged.
Read more: https://en.wikipedia.org/wiki/Metalloid
_______________________________ Today's selected anniversaries:
1779:
American Revolution: James Wilson and his colleagues were forced to defend themselves after a mob, angered by his successful legal defense of 23 people from exile, converged on his house, resulting in six deaths. https://en.wikipedia.org/wiki/James_Wilson
1895:
The first U.S. Open golf tournament was held on a nine-hole course at the Newport Country Club in Newport, Rhode Island. https://en.wikipedia.org/wiki/U.S._Open_(golf)
1958:
The new constitution establishing the French Fifth Republic, France's current political regime, was introduced. https://en.wikipedia.org/wiki/French_Fifth_Republic
1976:
British Rail's InterCity 125 service (pictured), the world's fastest diesel-powered train, began operations on the Western Region. https://en.wikipedia.org/wiki/InterCity_125
2010:
The dam holding a waste reservoir in western Hungary collapsed, freeing 1 million cubic metres (1,300,000 cu yd) of red mud, which flooded nearby communities and killed at least nine people. https://en.wikipedia.org/wiki/Ajka_alumina_plant_accident
_____________________________ Wiktionary's word of the day:
catloaf: The loaflike form of a domestic cat sitting with paws tucked underneath the body. https://en.wiktionary.org/wiki/catloaf
___________________________ Wikiquote quote of the day:
Buster survives tornados, waterfalls, avalanches of boulders, and falls from great heights, and never pauses to take a bow: He has his eye on his goal. And his movies, seen as a group, are like a sustained act of optimism in the face of adversity; surprising, how without asking, he earns our admiration and tenderness. Because he was funny, because he wore a porkpie hat, Keaton's physical skills are often undervalued … no silent star did more dangerous stunts than Buster Keaton. Instead of using doubles, he himself doubled for his actors, doing their stunts as well as his own. --Roger Ebert https://en.wikiquote.org/wiki/Roger_Ebert
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