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1- Who an when was aluminum discovered? Hans Christian discovered aluminum in 1825 in Denmark. []

1- ** Who / Where / When / How ** ** Discoverer: ** Hans Christian Oersted ** Discovery Location: ** Copenhagen Denmark ** Discovery Year: ** 1825 ** Name Origin: ** Latin: alumen (alun)

1. 1-Aluminum was named for one its most important compounds, alum. Alum is a compound of potassium, aluminum, sulfur, and oxygen. The chemical name is potassium aluminum sulfate, KAl(SO 4 ) 2.

No one is sure when alum was first used by humans. The ancient Greeks and Romans were familiar with the compound alum. It was mined in early Greece where it was sold to the Turks. The Turks used the compound to make a beautiful dye known as Turkey red. Records indicate that the Romans were using alum as early as the first century B.C.

Pure aluminum metal was finally produced in 1827 by German chemist Friedrich Wöhler (1800-82). Wöhler used a method perfected by English chemist Sir Humphry Davy (1778-1829), who succeeded in isolating several elements during his life-time. Wöhler heated a mixture of aluminum chloride and potassium metal. Being more active, the potassium. []

__ [|2.] __ __ [|2-The earth's crust] __ [|Aluminum] 8.23%82,300 All of the earth's aluminum has combined with other elements to form compounds. Two of the most common compounds are alum, such as potassium aluminum sulfate (KAl(SO4)2·12H2O), and aluminum oxide (Al2O3). About 8.2% of the earth's crust is composed of aluminum.

__http://education.jlab.org/itselemental/ele013.html__ 3-What is the chemical formula and structure of the compound? Describe how the bonds form.

1. The chemical formula is Al2O3. A metal atom* transfers its VALENCE electron to a  non metal atom* because of its low ionization energy. The metal atom loses an electron becoming a positive charged ion called a cation. The non metal atom gain an electron becoming a negatively charged ion called an anion. The opposite charges react forming an ionic bond. *metal atom: Al *non metal atom: O

The structure of Al2O3 is:



[|http://phycomp.technion.ac.il/~ira/types.html] My Learning log

3. 4:what are the structure and properties of airplane? ** Lightweight - Aluminum is about one-third the weight of an equal volume of copper, steel or brass. **

** Strength ** - Aluminum can withstand heavy loads and pressure.

** High strength-to-weight ratio ** - The ratio of the tensile strength of aluminum, divided by density, is higher than any other metal.

** Finishing ** - Aluminum can be finished with a variety of coatings and finishes such as paint, lacquer, porcelain or organic coatings.

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the structure is: Cubic….

[] 4. 5- What impact does aluminum have on society ? 1. Aluminum help society in two different ways. First way when people travel on airplane. They usually do that to visit their relatives and friends. Second way, using the power lines to transfer the electricity for all cities. People use electricity to open their telephone, computer, and charge their mobile, and all these are means of communication that keep attached with other people. This is who aluminum helped the society to grow up. 5. [] 6- 6. Advantage and disadvantages of using the materials in the airplane? 7.

Advantage

Disadvantage []

8. question 6 There are environmental impacts associated with each stage of aluminum production, from extraction to processing. The major environmental impact of refining and smelting is greenhouse gas emissions. These gases result from both the electrical consumption of smelters and the byproducts of processing. The greenhouse gases resulting from primary production include per fluorocarbons (PFC), polycyclic aromatic hydrocarbon (PAH), fluoride, sulfur dioxide (S02), and carbon dioxide (CO2). Of these gases, PFC's resulting from the smelting process are the most potent. Primary aluminum production is the leading source of per-fluorocarbon emissions in the United States. PAH emissions result from the manufacture of anodes for smelters and during the electrolytic process. Sulfur dioxide and sodium fluoride are emitted from smelters and electrical plants. SO2 is one of the primary precursors of acid rain. CO2 emissions occur during smelting and result from the consumption of carbon anodes and from PFC emissions.

The atmospheric pollutants from primary aluminum production also produce acid rain when they mix with water vapor. Aluminum poses no danger of environmental toxicity when soil pH remains at or above 5.0, however acid rain lowers the pH of soil and forces aluminum into solution. This causes it to leach into the water supply where it can damage root systems and create acidified lakes. Due to its natural abundance, the amount of aluminum that enters the environment due to regular weather processes far exceeds anthropogenic contributions.

Large amounts of aluminum can be toxic to humans, but high exposure levels are typically limited to miners, aluminum production workers, and dialysis patients. While there is some evidence linking aluminum to Alzheimer's disease, increased aluminum intake has yet to be a proven cause of the onset of Alzheimer's. Otherwise, aluminum is not significantly bioaccumulated in plants and animals.

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