Properties of Mercury

As one can see from the melting and boiling points (-38.7 C and 357 C, respectively), elemental mercury exists as a liquid at room temperature. Liquid mercury is very volatile (in fact the most of any metal), as seen from its very low vapor pressure of 0.00002 Pa @ -38.7 C. Even though this transition metal is a liquid, it is still conductive, with an electrical conductivity of 0.0104×106/cmΩ

and a thermal conductivity of 0.0834 W/cmK. Excited mercury atoms emit light in visible wavelengths, making it especially useful in light bulb applications.

Mercury readily forms amalgams, or solutions, with other metals. For example, an amalgam of mercury, tin and silver is used in dentistry. This tendency for mercury to form amalgams makes it especially dangerous to be handled by people wearing gold jewelry, as it can diffuse into the gold.

Mercury or "quicksilver" has been known since ancient times, distinctive because of its liquid form at room temperature. The name and symbol are taken from the Latin hydragyrus for "liquid silver". Of course, mercury is a good material for thermometers and barometers because it expands and contracts regularly with temperature, does not "wet" or stick to glass and is very dense. It is also used in special motion-sensitive switches and in ordinary fluorescent lamps.