What makes mercury a metal

Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements. Appearance The description of the element in its natural form. Biological role The role of the element in humans, animals and plants.

Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation. The image is of a traditional alchemical symbol for mercury. This is also an astrological symbol for the planet Mercury. The dragon or serpent in the background comes from early alchemical drawings and is often associated with the element.

Mercury has fascinated people for millennia, as a heavy liquid metal. However, because of its toxicity, many uses of mercury are being phased out or are under review.

It is now mainly used in the chemical industry as catalysts. It is also used in some electrical switches and rectifiers. Previously its major use was in the manufacture of sodium hydroxide and chlorine by electrolysis of brine. These plants will all be phased out by It was also commonly used in batteries, fluorescent lights, felt production, thermometers and barometers. Again, these uses have been phased out.

Mercury easily forms alloys, called amalgams, with other metals such as gold, silver and tin. The ease with which it amalgamates with gold made it useful in recovering gold from its ores.

Mercury amalgams were also used in dental fillings. Mercuric sulfide vermilion is a high-grade, bright-red paint pigment, but is very toxic so is now only used with great care.

Biological role. Mercury has no known biological role, but is present in every living thing and widespread in the environment. Every mouthful of food we eat contains a little mercury. Our daily intake is less than 0. However, in much higher doses it is toxic and one form of mercury — methylmercury — is particularly dangerous. It can accumulate in the flesh of fish and be eaten by people, making them ill.

Natural abundance. Mercury rarely occurs uncombined in nature, but can be found as droplets in cinnabar mercury sulfide ores.

China and Kyrgyzstan are the main producers of mercury. The metal is obtained by heating cinnabar in a current of air and condensing the vapour. Help text not available for this section currently. Elements and Periodic Table History. Cinnabar aka vermilion, mercury sulfide, HgS , was used as a bright red pigment by the Palaeolithic painters of 30, years ago to decorate caves in Spain and France. Cinnabar would yield up its mercury simply on heating in a crucible, and the metal fascinated people because it was a liquid that would dissolve gold.

The ancients used in on a large scale to extract alluvial gold from the sediment of rivers. The mercury dissolved the gold which could be reclaimed by distilling off the mercury. In the Americas, it was the Spanish conquerors who exploited the large deposits of cinnabar at Huancavelica in order to extract gold. Although highly toxic, mercury had many uses, as in thermometers, but these are now strictly curtained. Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom.

Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves.

Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.

Supply risk. Relative supply risk 8. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material.

Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated November 17, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. Copper Facts: Chemical and Physical Properties. Liquid Elements on the Periodic Table. Mercury is the only metal that is a liquid at normal temperatures and pressure.

Why is mercury a liquid? What makes this element so special? Basically, it's because mercury is bad at sharing—electrons, that is. Most metal atoms readily share valence electrons with other atoms.

The electrons in a mercury atom are bound more tightly than usual to the nucleus. In fact, the s electrons are moving so fast and close to the nucleus that they exhibit relativistic effects, behaving as if they were more massive than slower-moving electrons. It takes very little heat to overcome the weak binding between mercury atoms. Because of the behavior of the valence electrons , mercury has a low melting point, is a poor electrical and thermal conductor, and doesn't form diatomic mercury molecules in the gas phase.

The only other element on the periodic table that is a liquid at room temperature and pressure is the halogen bromine.

While mercury is the only liquid metal at room temperature, the elements gallium, cesium, and rubidium melt under slightly warmer conditions. If scientists ever synthesize a sufficient quantity of flerovium and copernicium, these elements are expected to have an even lower boiling point and perhaps melting point than mercury. The burning of coal, oil and wood as fuel can cause mercury to become airborne, as can burning wastes that contain mercury.

The amount of mercury deposited in a given area depends on how much mercury is released from local, regional, national, and international sources. Since mercury occurs naturally in coal and other fossil fuels, when people burn these fuels for energy, the mercury becomes airborne and goes into the atmosphere.

In the United States, power plants that burn coal to create electricity are the largest source of emissions; they account for about 44 percent of all manmade mercury emissions Source: National Emissions Inventory, version 2, Technical Support Document July pp, 10 MB, About PDF ; discussion starts on page of the PDF document.

The burning of municipal and medical waste was once a major source of mercury emissions. You can view a chart showing the annual amount of emissions of mercury and mercury compounds into the air from facilities throughout the United States from to Depending on these factors, mercury in the atmosphere can be transported over a range of distances -- anywhere from a few feet from its source, to halfway around the globe -- before it is deposited in soil or water. Mercury that remains in the air for prolonged periods of time and travels across continents is said to be in the "global cycle.

One major source of mercury emissions outside of the U. The main way that people are exposed to mercury is by eating fish and shellfish that have high levels of methylmercury, a highly toxic form of mercury, in their tissues. A less common way people are exposed to mercury is breathing mercury vapor. This can happen when mercury is released from a container, or from a product or device that breaks.

If the mercury is not immediately contained or cleaned up, it can evaporate, becoming an invisible, odorless, toxic vapor. Mercury exposure at high levels can harm the brain, heart, kidneys, lungs, and immune system of people of all ages. High levels of methylmercury in the bloodstream of babies developing in the womb and young children may harm their developing nervous systems, affecting their ability to think and learn.

Learn more about health effects that can result from exposures to mercury.