Mercury (also known as quicksilver) is a chemical element with the symbol Hg (from its latin name hydrargyrum) and atomic number 80. It is the only liquid metal at room temperature.
Mercury is resistant to most acids, although oxidizing acids such as concentrated sulfuric acid, nitric acid or aqua regia dissolve it to give sulfate, nitrate, and chloride salts. Mercury has two potential oxidation states (I) and (II). Mercury(I) nitrate, or mercurous nitrate, can be prepared by dissolving mercury in cold dilute nitric acid, while mercury(II) nitrate, mercuric nitrate, can be prepared by dissolving the metal in hot concentrated nitric acid. Like silver, mercury reacts with atmospheric hydrogen sulfide, but unlike silver will also react with solid sulfur, forming cinnabar (mercury sulfide). Elemental sulfur is used to absorb mercury spills and vapors. Mercury will also form amalgams with gold, aluminium or alkali metals.
Mercury is a dense, silvery-white liquid metal. It is a poor conductor of heat, but a fair conductor of electricity. Mercury melts point of −38.83 °C and boils at 356.73 °C. Unlike other metals that melt at low temperatures, liquid mercury in does not wet glass.
Mercury can be found in medical mercury thermometers. Old tilt switches also have mercury. In EU the sale of mercury is restricted.
Mercury can be prepared by reducing its salt with a reducing metal (though it's best avoiding metals that form amalgam). Reducing it's sulfide can generate toxic mercury vapors.
Not unless you have a damn good lab.
Elemental mercury in its liquid form is not very reactive, but its vapors and compounds are extremely toxic. Mercury ions have a long half life in the body, and are potent cumulative toxins. If the metal is dropped onto a porous surface, such as wood, the metal can split into micron-sized beads which will evaporate and fill the room with extremely toxic mercury vapor. Many compounds can rapidly absorb through the skin and cause severe mercury poisoning. This leads to severe medical problems and can eventually lead to death, usually after a longer period of time.