Learn about Mercury and what it can do!


Mercury (Hg), is an element that has been used to clean wounds and has been found in Egyptian tombs 3 500 years old. It is primarily found in the ore cinnibar (HgS). Italy and Spain produce about half of the world's amount of mercury, helping make thermometers, lamps, barometers and other scientific tools.


Mercury's chemical symbol comes from the Greek word hydrargyrum, which means "liquid silver."

Mercury is the only metal that is a liquid at room temperature, though it is the poorest conductor of heat among other metallic elements. So how is it used in thermometers? The reason being is because even the slightest change of temperature will cause the element to move due to its high expansion rate. It also has a very high boiling point making it very convenient for measuring high temperatures and the liquid form of this element won't stick on slick surfaces such as glass.

The only way to get pure mercury is to extract it from the ore it is within, primarily cinnabar. Scientists heat the ore up at about 1,076 degrees F, and then mercury vapor comes out. This is very dangerous as mercury is very poisonous to the human body especially when inhaled. They then condense it and purify it with nitric acid.

Mercury forms useful compounds with other elements. Mercuric chloride (HgCl2) is a very poisonous salt and was once used to disinfect wounds. Mercurous chloride (Hg2Cl2), also called calomel, is an antiseptic used to kill bacteria. Mercuric sulfide (HgS) is used to make a red paint pigment called vermilion. Mercuric oxide (HgO) is used to make mercury batteries.

Mercury can form interesting alloys with other metals. These alloys allow the extracting of gold from rock. When mercury comes into contact with gold, the gold dissolves into the mercury and is then separated.