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Gaffer Variety:
Elements 16 SN2 018:
By Willie Gaffer:
Nickel:
Nickel, Symbol Ni, is a silvery, hard, ductile, ferromagnetic metallic element. It is used in alloys, corrosion-resistant surfaces, and nickel cadmium batteries. The atomic number is 28, the atomic weight is 58.71, the melting point is 1,453°C, the boiling point is 2,732°C, and the specific gravity is 8.902. Nickel has valences of 0, 1, 2, 3 and it occupies group 10B of the periodic table. The electron shell configuration is 2, 8, 16, and 2.
Nickel was discovered by the Swedish chemist Axel Fredrik
Cronstedt way back in 1751. He discovered it was an element in the mineral
niccolite. That was then. Now most nickel is extracted from another mineral,
pentlandite. Most of the world's supply of nickel is mined in
Nickel is a corrosion resistant metal so it can be used in electroplating of other metals. The plating give other metals a corrosion resitant coating. Nickel is also used as a catalyst in the food industry for the hydrogenation of vegetable oils. Other uses are in glass manufacturing, wire, and coins.
Nickel can be alloyed with other metals to improve their strength and resistance to corrosion. For example, with steel to make a very strong alloy for armor plates and machine parts. With copper it is used to make corrosion resistant pipes. Very powerful permanent magnets are made from an alloy of aluminum, nickel, cobalt and iron.
Copper:
Copper, Symbol Cu, is a ductile, malleable, reddish-brown metallic element that is an excellent conductor of heat and electricity and is widely used for electrical wiring, water piping, and brass. Brass is an alloy of copper and zinc. Another alloy, bronze, is an alloy of copper and tin, sometimes with other elements. The atomic number is 29, the atomic weight is 63.54, the melting point is 1,083°C, the boiling point 2,595°C, and the specific gravity is 8.96. Copper has valences of 1 and 2 and we find it in group 11B of the periodic table. The electron shell configuration 2, 8, 18, and 1.
Copper was probably the first known metal to mankind. We find that the ages of man includes a period some times called the Copper Stone Age which occurred somewhere in the New Stone Age. This is hard to pinpoint as it quickly evolved into the Bronze Age. We can place it approximately between 8000, and 6000 BC. Copper was the first metal used by man because it could be found in its pure form. The discovery of bronze, which is an alloy of copper and tin, took a bit longer. Bronze however being harder is much superior for weaponry and copper was quickly abandoned.
Probably the major user of copper is the electrical industry because of its high conductivity. Most electrical wire is made from copper. Silver is better in conductivity, but it is prohibitively expensive for such mundane uses as wire. There were some attempts by the aluminum industry to displace copper from its dominance in electrical devices, but aluminum presented other problems and the attempt was abandoned.
Copper is also used in coins. The American penny was originally copper. Now, the penny is a cheaper substitute made of zinc and plated with copper. Copper has been used to make jewelry and some people claim the metal has inherent curative powers. They wear copper bracelets on their wrists. The major power I have notices is the ability to turn green in the presence of perspiration and turn the skin green too.
Zinc:
Zinc, symbol Zn, is a bluish-white, lustrous metallic element that is brittle at room temperature but malleable with heating. It is used to form a wide variety of alloys including brass, bronze, various solders, and nickel silver. The atomic number is 30, the atomic weight is 65.37, the melting point is 419.4°C, the boiling point is 907°C, and the specific gravity is 7.133 (25°C). Zinc has a valence of 2 and it is found in group 12B of the periodic table. The electron shell configuration is 2, 8, 18, and 2.
About one third of all zinc produced is used in a process known as galvanization. This is a process of coating a metal, usually iron or steel, with a protective coating of zinc. Galvanized iron is usually prepared by dipping or electroplating. The most common method is electroplating wherein zinc anodes are used in an electrical process where the zinc anode is dissolved and a layer of zinc is deposited on the recipient cathode metal. Metallic zinc is also used to make dry cell batteries, roof cladding and die castings.
Zinc is used to make many useful alloys. Brass, as mentioned above is an alloy of zinc that contains between 55% and 95% copper, is probably the best known zinc alloy. Brass was widely used by the ancient Romans to make such things as coins, kettles, and decorative items. Brass is still used today, particularly in musical instruments, screws and other hardware that must resist corrosion.