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Where are metals located on the periodic table?
Periodic table
The elements can be conveniently classified according to their shared physical and chemical properties into the major categories of metals, metalloids and nonmetals. Metals are generally located to the left and bottom of the periodic table. They are ordinarily shiny, highly conducting solids which form alloys with one another and salt-like ionic compounds with nonmetals. Nonmetals are located to the right and top. They are mostly coloured or colourless insulating gases that form covalent compounds with one another. In between metals and nonmetals are metalloids, which have intermediate or mixed properties. Metal and nonmetals can be further classified into similar subcategories that show a left to right gradation in metallic to non-metallic properties. The metals are divided into the highly reactive alkali metals, through the less reactive alkaline earth metals, lanthanides and actinides, via the archetypal transition metals, and ending in the physically and chemically weak other metals. The nonmetals are simply subdivided into the polyatomic nonmetals which, being nearest the metalloids, show some incipient metallic character; the diatomic nonmetals, which are essentially nonmetallic; and the monatomic noble gases, which are almost completely inert and nonmetallic. Specialized groupings such as the refractory metals and the noble metals, which are subsets (in this example) of the transition metals, are also known and occasionally denoted. Placing the elements into categories and subcategories based on shared properties is imperfect. There is a spectrum of properties within each category and it is not hard to find overlaps at the boundaries, as is the case with most classification schemes. Beryllium, for example, is classified as an alkaline earth metal although its amphoteric chemistry and tendency to mostly form covalent compounds are both attributes of a chemically weak or other metal. Radon is classified as a nonmetal and a noble gas yet has some cationic chemistry that is more characteristic of a metal. Other classification schemes are possible such as the division of the elements into mineralogical occurrence categories, or crystalline structures. Categorising the elements in this fashion dates back to at least 1869 when Hinrichs wrote that simple boundary lines could be drawn on the periodic table to show elements having like properties, such as the metals and the nonmetals, or the gaseous elements.