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The earliest gold metallurgy is known from the Varna culture in Bulgaria, dating from c. 4600 BC. [6] Silver, copper, tin and meteoric iron can also be found native, allowing a limited amount of metalworking in ancient cultures. [7] Egyptian weapons made from meteoric iron in about 3000 BC were highly prized as "daggers from Heaven". [8]
Wax candle. Waxes such as paraffin wax or beeswax, and hard fats such as tallow are used to make candles, used for lighting and decoration. Another fuel type used in candle manufacturing includes soy. Soy wax is made by the hydrogenation process using soybean oil.
Nickel ions can act as a cation in salts with many acids, including common oxoacids. Salts of the hexaaqua ion (Ni · 6 H 2 O 2+) are especially well known. Many double salts containing nickel with another cation are known. There are organic acid salts. Nickel can be part of a negatively charged ion (anion) making what is called a nickellate.
Spheres of nickel made by the Mond process The Mond process , sometimes known as the carbonyl process , is a technique created by Ludwig Mond in 1890, [ 1 ] to extract and purify nickel . The process was used commercially before the end of the 19th century, [ 2 ] and particularly by the International Nickel Company in the Sudbury Basin . [ 3 ]
Nickel can be in different or even mixed oxidation states, ranging from +1, +2, +3 to +4. The anions can contain a single nickel ion, or multiple to form a cluster ion. The solid mixed oxide compounds are often ceramics, but can also be metallic. They have a variety of electrical and magnetic properties.
Major (iron, manganese, magnesium and zinc) and minor (copper, cobalt, nickel, molybdenum, tungsten) metal ions have become aligned with living organisms through the interplay of biogeochemical weathering and metabolic pathways involving the products of that weathering. The associated complexes have evolved over time.
These rays, which he discovered but were later called cathode rays by Eugen Goldstein, produced a fluorescence when they hit a tube's glass walls and, when interrupted by a solid object, cast a shadow. 1869: William Crookes: Invented the Crookes tube. 1873: Willoughby Smith: Discovered the photoelectric effect in metals not in solution (i.e ...
Carl Wilhelm Scheele (German:, Swedish: [ˈɧêːlɛ]; 9 December 1742 – 21 May 1786 [2]) was a German Swedish [3] pharmaceutical chemist.. Scheele discovered oxygen (although Joseph Priestley published his findings first), and identified molybdenum, tungsten, barium, nitrogen, and chlorine, among others.