1. Mercury Laura Rogers Chemistry 12 – A Block Mrs.McLellan

2. Mercury Hg Hg is the symbol for Hydrargyrum, which translates to liquid silver Transition Metal Can have the charge +1 or +2 Atomic mass is 200.6 Electronegativity is 1.9 Atomic number is 80 Either one or two valance electrons

3. Properties of Mercury Mercury is: Metal – transition metal Liquid at room temperature Heavy Silver in colour When poured on smooth surfaces, it rolls around and forms into little balls Melting point of 38.842°C Boiling point of 356.58°C Fair conductor of electricity Poor conductor of heat Very poisonous when vaporized

4. Where is mercury is found? Mercury is rarely found free in nature Mercury is extracted from ore, and is often used to purify silver and gold Mercury exists in the form of a red ore called cinnabar that is composed of mercury and sulfur In the Earth’s crust mercury is not easily found compared to other elements, yet it is not considered rare, because when it is found there are large amounts and in high concentration

5. Methylmercury Microorganisms turn mercury into methymercury which is highly toxic Very toxic Organic form of mercury Methlymercury is the cause of mercury poisoning Easily absorbed into aquatic species tissue, but not easily removed Animals higher on the food chain contain higher amounts of methylmercury

6. Mercury Poisoning Mercury is highly poisonous and causes nerve damage Mercury is released into the air when coal is burned After being in the air the mercury settles into the land and water If it gets on ones unbroken skin, or inhaled it is absorbed very quickly, very easily absorbs into the air, which people breathe in then get poisoned… There are acute and chronic forms of mercury poisoning: Acute – less common in present day – cause ulcers in the stomach and intestine lining, harms ones kidney and ability to urinate Chronic – causes diarrhea, slow reflexes, tremor, poor coordination and impaired vision The brain is the most susceptible organ to be affected

7. More Mercury Poisoning People have died from mercury poisoning in the past and in present day In the 1800s mercury salt was used on hats, which poisoned and killed people. “Mad as hatters” is derived from this In the present day mercury poisoning is usually due to food intake In Minimata Bay, Japan thousands were posited and lost their lives due to contaminated fish Minimata Disease is caused by methlymercury poisoning Other deaths have been caused by: Flour made from seed grain treated with methylmercury that affected 6500 people in Iraq Meat from animals raised on mercury-tainted grain in America and New Mexico Unborn children are also at risk of mercury poisoning Methylmercury travels to the placenta from mother to the fetus Children born with Minimata diseasemaychavegrowth deficiency,severe mental problems, an abnormally small head, be blind or deaf

8. “The U.S. Food and Drug Administration (FDA) as of 1999 recommends limiting consumption to 1 kilogram (2.2 pounds) of fish and shellfish a week and considers 1 part per million of mercury in seafood to be safe. However, top predator fish such as shark and swordfish can have mercury concentrations over 1 part per million. The FDA recommends no more than one serving a week of these two fish for most people and no more than one serving a month for pregnant or nursing women or those who may become pregnant.” http://www.medterms.com/script/main/art.asp?articlekey=10991

9. Mercury in the water table Mercury is released into the air when large amounts of coal are burned to make energy Once the mercury is in the air, it gets into the water table The mercury builds up in sea creatures like fish and shellfish In certain, more acidic bodies of water there are higher amounts of mercury When the pH levels are between 7 and 5, the mercury concentrations in the water will increase due to movement of mercury in the ground Then microorganisms convert the mercury into methylmercury, which makes it easier to absorb

10. What not to do with mercury Do NOT: Sweep – it will break up the mercury into smaller pieces, increasing the surface area making more go into the air Vacuum – it will release the mercury into the air and increase the mercury level Wash mercury contaminated clothing – it will contaminate your washer, all the clothes, the water, and when the clothes are put in the dryer the mercury will be released into the air Pour it down the drain – it will pollute your septic tank, clog your drain and get into the water table Eat a lot of fish when you are pregnant

11. Uses for mercury Thermometers Diffusion pumps Barometers Mercury vapor lamps Mercury switches Pesticides Batteries