Dr Sharipah Ruzaina Syed Aris Symbols, formula, Periodic Table, Avogadro number
Symbols: Abbreviations for the chemical elements
Atomic Symbols, Isotopes, Numbers X = Atomic symbol of the element A = mass number; A = Z + N Isotope = atoms of an element with the same number of protons, but a different number of neutrons A Z Z = atomic number (the number of protons in the nucleus) N = number of neutrons in the nucleus X The Symbol of the Atom or Isotope
chromium. Metallic element discovered independently by Louis-Nicolas Vauquelin (1763–1829) and Martin Heinrich Klaproth (1743–1817) in 1798, but not isolated until 1859 by Friedrich Wöhler (1800–82). Despite its attractive, bright, shiny, silvery appearance, and its reluctance to corrode, it was not much used until it was employed in the armaments industry during the 1914–18 war. From the 1920s it was produced commercially, and was used for plating on steel or copper (notably for the automobile industry), and was favoured by several Modernist architects for both buildings (e.g. Mies van der Rohe for the casings of columns in both the Barcelona Pavilion and the Tugendhat House) and furniture (e.g. the tubular steel frames of chairs of the period). It was widely used for Art-Deco work .