MERCURY
Mercury is a metallic element that is a liquid at room temperature, it is one of the
transition elements. Mercury's atomic number is 80. It is superconductive when cooled
to within a few degrees of absolute zero. Mercury was once known as liquid silver or
quicksilver which was studied by the alchemists. Mercury was first distinguished as an
element by the French chemist Antoine Laurent Lavoisier in his experiment on the
composition of air. At room temperature mercury is a shining, moving liquid that has a
silvery-white color, and slightly volatile. Mercury remains a liquid over a wide
temperature range. Mercury is a solid when given a pressure of 7640 atmospheres (5.8
million torrs). It dissolves in nitric or concentrated sulfuric acid but is resistant to
alkalies. Mercury melts at -39C, boils at about 357C,and has a gravity of 13.5. The
atomic weight of mercury is 200.59. Mercury comes in its pure form or combined with
silver in small amounts. It is mostly found in the form of the sulfide.
Mercury has many uses and is a very important element. A major use of mercury is in
electrical equipment such as fluorescent lamps, and mercury batteries. Mercury is used
in thermometers because the change in volume for each degree of rise or fall in
temperature is the same. The use of mercury in the thermometer instead of alcohol was
done by Gabriel Daniel Fahrenheit in 1714. It was also used in vacuum pumps, barometers,
and electric rectifiers and switches. Mercury is used in a mercury-vapor lamps which are
used as a source of ultraviolet rays in homes and for sterilizing water. Mercury-vapor
is also used instead of steam in the boilers of some turbine engines. Mercury is
sometimes used for amalgamation. Amalgamation is a metallurgical process that utilizes
mercury to dissolve silver or gold to form an amalgam. This process has been largely
supplanted by the cyanide process, in which gold or silver is dissolved in solutions of
sodium or potassium cyanide.
Mercury is a poisonous element. Mercury is semi hazardous as a vapor and Among the many
good things mercury does for people there is a flip side. in the form of its
water-soluble salts. Chronic mercury poisoning, which occurs when small amounts of the
metal are repeatedly ingested over long periods of time, causes irreversible brain,
liver, and kidney damage.
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