The Reactivity of A Metal and When it Was Discovered. Alia Al-Khater. Introduction.
Although most metals are usually electropositive in nature and lose electrons in a chemical reaction they do not react with the same vigor or speed. Metals display different reactions towards different substances. The greater the ease with which an element loses its electrons and acquires a positive charge, the greater is its reactivity. Further, the greater the number of shells and lesser the number of valence electrons, the greater is the reactivity of the metal.
Currently there are 86 known metals. Before the 19th century only 24 of these metals had been discovered andof these 24 metals, 12 were discovered in the 18th century. Therefore, from the discovery of the first metals - gold and copper until the end of the 17th century, some 7700 years, only 12 metals were known.
- Metals of antiquity refers to the seven metals which humankind had identified and found use for in prehistoric times. These seven metals, gold, copper, silver, lead tin, iron, and mercury, are the seven metals upon which modern civilization.
4) "Histiry of Metals." METAL WEB NEWS. Web. 10 Nov. 2010. <http://www.metalwebnews.com/metals-history.html>.
5) "Metals Timeline." Www.ic.arizona.edu. Web. 10 Nov. 2010. <http://www.ic.arizona.edu/ic/mse257/class_notes/metals_timeline.html>.