| cobalt is used for alloys, isotopes, compounds, you can make tv sets,
drilling bits, cutting tools, gas turbines and jet engines. Discovered
in 1735, cobalt occurs most frequently as the sulfide in deposits of cobalt
ores such as cobaltite, CoAsS, and smaltite, CoAs2. Cobalt is magnetic.
The metal is obtained in greatest quantity as a byproduct of the extraction
of nickel, copper, and lead from their ores.
The metal itself is relatively unreactive. Exposure to high temperature
moist air gradually converts the metal to the oxide, CoO. This oxide
is used to produce a deep blue color in glasses, potteries, tiles,
porcelain, and paints.
Cobalt is used in some specialty alloys, alnico. Permanent magnets
are made with such an alloy that contains 8% aluminum, 14% nickel, 24%
cobalt, 3% copper, and 51% iron. Other alloys with chromium and tungsten
are used for surgical instruments. Some are used in making jet engines.
Many cobalt compounds are also used as contact catalysts for organic
reactions. A radioactive isotope of cobalt is used to treat cancer.
In 1935, it was established that traces of cobalt are essential to humans.
Cobalt is present in meat, dairy products and in vitamin B12, which prevents
pernicious anemia. Cobalt is also needed for the growth of many animals.
Cobalt is usually supplied by soil and fertilizers. |
