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Science Fair Projects for 4th Grade400 award winning science fair projects here. Try one of these proven winners for your next science fair. Make science fun with a winning project. What holds your interest -- living green & the environment, astrology, aircraft? There is a great science fair idea in all these topics. The trick to a winning science fair project is to choose a topic you like and find a project to match it. Take a look at these fun science fair project ideas. Start your science fair project today. Each science fair project includes about 15 pages of easy-to-follow directions to help you create your project step-by-step.
As a bonus, every project includes 16 free original science games that you can play with all your friends! In addition to these winning science fair ideas, you can choose from over 400 other science fair project ideas. Every subject is covered including chemistry, physics, biology, computer and environmental sciences, and more. Choose it and print it now; start your science fair project right away!
Background information about rust that you may find useful for your science fair project. Rust is the substance formed when iron compounds corrode in the presence of water and oxygen. It is a mixture of iron oxides and hydroxides. Iron is found naturally in the ore, hematite, as iron oxide, and purified iron quickly returns to a similar state when exposed to air and water. This corrosion is due to the oxidation of a metal being an energetically favorable process--energy is given off when rust forms. When an iron compound comes into contact with a drop of water, an electrochemical process starts. The process of rusting can be summarized as three basic stages: 1) The formation of iron ions from the metal, 2) The formation of hydroxide ions, and 3) Their reaction together, with the addition of oxygen, to create rust. On the surface of the metal, iron is oxidized to iron. The formula for this is:
Fe -> Fe2+ + 2e-
The electrons released travel to the edges of the water droplet where there is plenty of dissolved oxygen. They reduce the oxygen and water to hydroxide ions:
2e- + 1/2O2 + H2O -> OH-
The hydroxide ions react with the iron ions and more dissolved oxygen to form iron oxide. The hydration is variable (with x water molecules surrounding each iron oxide molecule):
Fe2+ + 2OH- -> Fe2O3xH2O
Rusting tends to happen faster at sea. This is due to the higher concentration of sodium chloride ions in the water, making the solution more conductive. Rusting is also accelerated in the presence of acids, and inhibited by alkalis. Unfortunately rust is unlike aluminum oxide, which forms a protective coating on aluminum to prevent further oxidation.
Hydrated iron oxide is permeable to air and water, meaning that the metal continues to corrode after rust has formed. However there exist a number of ways of stopping, or slowing, this process.
Galvanizing is coating the metal with a thin layer of another metal, such as zinc, which forms a protective oxide. The two most common processes used to achieve this are hot-dip galvanizing and electrogalvanizing.
Also used are sacrificial metals attached through a conductor to the metal at risk. As the sacrificial metal is chosen to have a higher electrode potential, it is oxidized in preference to the iron.
Electrons conduct to the site attacked by oxygen and water and reduce oxygen to hydroxide irons as in normal rusting. Because there are no iron ions to react with the hydroxide ions, no rust is formed. Other techniques of preventing rust include the coating of the metal in an organic polymer or paint. Unfortunately, these are not so powerful. If the surface is scratched, the metal is exposed and rust can still form.
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