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Gaffer Variety:
Elements 15 SN2 017:
By Willie Gaffer:
Manganese:
Manganese, symbol Mn, is a gray-white or silvery brittle metallic element, occurring in several allotropic forms, found worldwide, especially in the ores pyrolusite and rhodochrosite and in nodules on the ocean floor. The atomic number is 25, the atomic weight is 54.9380, the melting point is 1,244°C, the boiling point is 1,962°Cand the specific gravity can range from 7.21 to 7.44. The electron shell arrangement is 2, 8, 13, 2 and the valences are 1, 2, 3, 4, 6, and 7. It lives in group 7B of the periodic table.
Manganese can be alloyed with steel to increase strength,
hardness, wear resistance, and other properties and with other metals to form
highly ferromagnetic materials. That means it has the ability to become highly
magnetized in relatively weak magnetic fields. Although the metal does not
occur in the
It is alloyed with iron to make very tough alloy which is very resistant to wear. It is also used to make a form of bronze that resists corrosion. Hence, it can be used to make the underwater parts of boats, like propellers. Manganese dioxide is used in dry batteries, Paints, varnish, glass making, and ceramics. Manganese sulfate is used in fabric dyes.
Iron:
Iron, symbol Fe, is a silvery-white, lustrous, malleable, ductile, magnetic metallic element occurring abundantly in combined forms, notably in hematite, limonite, magnetite, and taconite, and used alloyed in a wide range of important structural materials. The atomic number is 26, the atomic weight is 55.847, the melting point is 1,535°C, the boiling point 2,750°C, and the specific gravity is 7.874 (at 20°C)Iron has valences of valence 2, 3, 4, and 6 with an electron shell arrangement of 2, 8, 14, 2. It occupies group 8B of the periodic table.
Iron is very abundant. It makes up 5 percent of the Earth's crust making it second to aluminum. It is also the major component of the Earth's core. It is also found in quantity in the Sun and other stars. Although it is rarely found in free form, nickel-iron which is a natural alloy, occurs in deposits. It is also found combined with other elements in many of minerals. The metal is extracted from the ore by smelting with carbon (coke) and limestone. For specific information on the mining and production of iron, see Industries, Extraction and Processing: Iron.
There is iron in all animals and, of course, in pretty much everything we eat. In humans, 65% of the iron shows up as hemoglobin. This is the component which makes our blood read and is responsible for moving oxygen around the body. Without enough of this stuff, we end up with a medical condition called anemia. We usually treat this condition with injections of vitamin B12. This is a chemical compound which is also called cobalamin because it contains cobalt. This is essential to the formation of blood cells. It is a coenzyme that assists the enzymes responsible for moving folate into the cell interior. In serious case of anemia direct injections of iron are sometimes used.
Iron nearly always contains small amounts of carbon, which
are picked up from the coke during smelting. These modify its properties, from hard
and brittle cast irons containing up to 4 percent carbon to more malleable
low-carbon steels containing less than 0.1 percent carbon. There are three know oxides of iron,
these being ferrous oxide, iron oxide, and ferric oxide. Perhaps the most common
form of ferric oxide is what we call rust, one of the main products of
There is little need to elaborate on the necessity of iron in industrial nations. All we need do is look around to see it is essential to civilization. Without it, we would have no navy, no guns (hmmm!), no auto industry, no skyscrapers, and we would all be eating with chopsticks or our hands.
Cobalt:
Cobalt, symbol Co, is a hard, brittle metallic element found associated with nickel, silver, lead, copper, and iron ores and resembling nickel and iron in appearance. It is used chiefly for magnetic alloys, high-temperature alloys, and in the form of its salts for blue glass and ceramic pigments. The atomic number is 27, the atomic weight is 58.9332, the melting point is 1,495°C;, the boiling point is 2,900°Cand the specific gravity is 8.9. It has valences of 2 and 3 with an electron shell configuration of 2, 8, 15, 2. It occupies group 9B of the periodic table.
Cobalt is fairly abundant in the earths crust ranking about 30. It occurs in several forms such as arsenide cobalt, cobalt sulpharsenide, and hydrated arsenate of cobalt. The radioactive cobalt-60 is the one of the most useful radioactive elements. It is used in industry and in radioisotope therapy as a tracer. Cobalt is also used to make what are called thermally resistant alloys, meaning they can tolerate extremes of temperature while maintaining their structural integrity. Other uses for alloys are as permanent magnets when alloyed with steel. It can also be alloyed with tungsten to make a product called Caboloy used in making cutting tools.