Mercury is a transition metal, one of the elements found in the middle of the periodic table in Rows 4, 5, and 6 between Groups 2 and 3. Its atomic number if 80, its atomic mass is 200.59, and its chemical symbol is Hg.

Properties

Mercury is the only liquid metal and the only liquid element except for bromine. Mercury has a freezing point of -37.93°F (-38.85°C), a boiling point of 673.9°F (356.6°C), and a density of 13.59 grams per cubic centimeter.

Two physical properties of special interest are mercury's high surface tension and its superior ability to conduct an electric current. The metal's surface tension is great enough to permit a steel needle to be floated on its surface. Its ability to conduct an electric current allows the metal to be used in a "mercury switch," a small glass capsule in which the metal can flow from one end...