Mercury (IPA: /ˈmɜrkjʊri/),
also called quicksilver or hydrargyrum,
is a chemical element
with the symbol Hg (Latinized Greek: hydrargyrum,
meaning watery or liquid silver) and atomic number 80. A heavy, silvery d-block metal, mercury is one of five metals that
are liquid at or near room temperature
and pressure. The others are the metals caesium, francium, gallium, and rubidium, and the non-metal bromine. Of these, only mercury and bromine are liquids at standard conditions for temperature and pressure.
Mercury is used in thermometers, barometers, manometers, sphygmomanometers,
and other scientific apparatus, though concerns about the element's
toxicity have led to mercury thermometers and sphygmomanometers being
largely phased out in clinical environments in favour of alcohol-filled, digital, or thermistor-based instruments. It remains in
use in a number of other ways in scientific and scientific research
applications, and in amalgam material for dental restoration.
Mercury is mostly obtained by reduction from the mineral cinnabar.
Mercury occurs in deposits throughout the world and it
is harmless in an insoluble form, such as mercuric sulfide,
but it is poisonous in soluble forms such as mercuric chloride