Monday, December 2, 2013

Chemistry Element Paper

November 29, 2013
Zirconium
By: Autumn Gwinn




Information About Zirconium
-Element Symbol: Zr
-Atomic Number: 40
-Atomic Mass: 91.22
-Density at 20°C: 6.49
-Melting Point: 1852°C
-Boiling Point: 4400°C
-1st Ionization Energy: 669

The History Behind Zirconium                   

Zircon, jargoon, hyacinth, jacinth, and ligure, elements that contain zirconium, were mentioned in biblical writings. Zirconium was not discovered until 1824 in an impure form. A German chemist, named Martin Heinrich Klaproth, analyzed jargoon from the island of Ceylon (now Sri Lanka) and discovered a new element. He named it zirconia. Humphry Davy, an English chemist, tried electrolysis on it and failed in his attempt. In 1824, Berzelius, a Swedish chemist, heated a mixture of potassium and potassium zirconium fluoride and revealed zirconium.

PHYSICAL AND CHEMICAL CHARACTERISTICS

Zirconium is a very strong, malleable, ductile, lustrous silver-gray metal. Its physical and chemical properties are similar to titanium. Its hardness is similar to copper. It is solid at room temperature and becomes hard and brittle at lower purities. Its powder form is black and very flammable, especially in high temperatures. It’s regarded as a very dangerous fire hazard. The solid form isn’t as prone to ignite. Zirconium is very resistant to heat and corrosion by alkalis, acids, salt water, and other substances. However, it will dissolve in hydrochloric and sulfuric acid, especially when fluorine is present.

ZIRCONIUM IN THE ENVIRONMENT

Zirconium is not really rare. It’s more than twice as abundant as copper and zinc and more than ten times more abundant than lead. Zirconium’s chief ores are zircon (mined in Australia, USA, and Sri Lanka) and baddeleyite, also known as zirconium oxide (mined in Brazil). Australia, South Africa, India, Sri Lanka, and the USA have vast deposits of zircon and zirconia sands.
HEALTH AND ENVIRONMENTAL EFFECTS
Zirconium and its salts generally have low toxic effects on the

body. The estimated dietary intake is about fifty micro grams. Most of it passes through the stomach without being absorbed. When it is absorbed, it tends to accumulate slightly more in the skeleton rather than in tissue. Short- term exposure to zirconium powder can cause irritation. The only time medical attention is required is when it comes in contact with eyes. Inhalation of certain zirconium compounds can cause skin and lung irritation, resulting in abnormal growths called granulomas. Long- term exposure to a form of zirconium called zirconium tetrachloride resulted in mortality in rats and guinea pigs and a decrease of hemoglobin in dogs. Zirconium is unlikely to present a hazard to the environment. Aquatic plants have a rapid uptake of soluble zirconium and land plants have little tendency to absorb it. 70% of plants that have been tested showed no zirconium present. When there was some present, it was very miniscule.

MATERIALS AND USES OF ZIRCONIUM

                                                                  Zirconium is used for all kinds of things. It’s used as a structural material in nuclear reactors. It’s used for removing gas residue from electronic vacuum tubes. It can be used as a hardening agent in alloys, such as steel. Also, it can be used in alloys for excellent water resistance. Materials fabricated from zirconium oxide are used in space vehicle parts for its resistance to heat. It’s used for furnace bricks, photographic flashbulbs, surgical instruments, and the glass for television. The most common thing people know is cubic zirconia, which is a diamond substitute in jewelry. It’s used in jewelry making because of its fracture toughness and chemical resistance.

THE COST TO OBTAIN
The cost of pure zirconium is $157 per 100 grams. The cost for bulk is $16 per 100 grams.