Elements Less Commonly Recognized As Metalloids
There is no universally agreed or rigorous definition of the term metalloid. So the answer to the question "Which elements are metalloids?" can vary, depending on the author and their inclusion criteria. Emsley, for example, recognized only four: germanium, arsenic, antimony and tellurium. James et al., on the other hand, listed twelve: boron, carbon, silicon, germanium, arsenic, selenium, antimony, tellurium, bismuth, polonium, ununpentium and livermorium. As of 2011 the list of metalloid lists recorded an average of just over seven elements classified as metalloids, per list of metalloids, based on a sample size of 194 lists.
The absence of a standardized division of the elements into metals, metalloids and nonmetals is not necessarily an issue. There is a more or less continuous progression from the metallic to the nonmetallic. A specified subset of this continuum can potentially serve its particular purpose as well as any other. In any event, individual metalloid classification arrangements tend to share common ground (as described above) with most variations occurring around the indistinct margins, as surveyed below.
Read more about this topic: Metalloid
Famous quotes containing the words elements, commonly and/or recognized:
“It is a life-and-death conflict between all those grand, universal, man-respecting principles which we call by the comprehensive term democracy, and all those partial, person-respecting, class-favoring elements which we group together under that silver-slippered word aristocracy. If this war does not mean that, it means nothing.”
—Antoinette Brown Blackwell (1825–1921)
“Smooth your way to the head, through the heart. The way of reason is a good one; but it is commonly something longer, and perhaps not so sure.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“It used to be said that, socially speaking, Philadelphia asked who a person is, New York how much is he worth, and Boston what does he know. Nationally it has now become generally recognized that Boston Society has long cared even more than Philadelphia about the first point and has refined the asking of who a person is to the point of demanding to know who he was. Philadelphia asks about a man’s parents; Boston wants to know about his grandparents.”
—Cleveland Amory (b. 1917)