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rust is a good conductor as it has a flow of electrons that enetr the oxygen through particles.

FOR MORE INFOR CLICK HERE------------ RUST------

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+rust is a good conductor as it has a flow of electrons that enetr the oxygen through particles.
-{{otheruses2|Rust}}
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-{{steels}}
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-[[Image:RustChain.JPG|thumb|258px|right|Heavy rust on the links of a chain near the Golden Gate bridge in San Francisco; where it was continuously exposed to moisture and salt-laden air, causing surface breakdown, cracking, and flaking of the metal.]]
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-[[Image:Love_by_SillyPuttyEnemies.jpg|thumb|258px|right|Flaking paint, exposing a heart-shaped patch of surface rust on sheet-metal]]
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-[[Image:Rust screw.jpg|thumb|258px|right|A rusted (and dirt-encrusted) bolt; note the surface pitting and gradual shape-deformation, caused by severe oxidation]]
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-[[Image:Removing rust with sand.jpg|thumb|258px|A [[blacksmith]] removing rust with sand prior to welding]]
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-[[Image:Rusted floorboards.jpg|thumb|258px|Rust damage in automobiles can create hidden dangers.]]
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-[[Image:Rust03102006.JPG|thumb|258px|Rusting can completely degrade iron. Note the [[galvanization]] on the unrusted portions.]]
-[[Image:Rust from bathtub in Kyiv.jpg|thumb|258px|Rust in pipes can result in brown and black water.]]
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+FOR MORE INFOR CLICK
-'''Rust''' is a general term for a series of [[iron oxides]], usually red oxides, formed by the reaction of [[iron]] and [[oxygen]] in the presence of water or air moisture.  Several forms of rust are distinguishable visually and by [[spectroscopy]], and form under different circumstances.<ref>{{cite web|url=http://nasa.gov/centers/ames/multimedia/audio/MER/mer13.html|title=Interview, David Des Marais}}</ref>  Rust consists of hydrated [[iron(III) oxide]]s Fe<sub>2</sub>O<sub>3</sub>·nH<sub>2</sub>O and [[iron(III) oxide-hydroxide]] (FeO(OH), Fe(OH)<sub>3</sub>). Rusting is the common term for [[corrosion]] of iron and its alloys, such as [[steel]]. Other metals undergo equivalent corrosion, but the resulting oxides are not commonly called rust.  Given sufficient time, oxygen, and water, any iron mass eventually converts entirely to rust and disintegrates. The corrosion of [[aluminium]] is extremely slow because the resulting  [[aluminium oxide]] forms a conformal coating, which protects the remaining aluminium. This process is known as [[passivation]].
+HERE------------ RUST------
-==Chemical reactions==
-===The oxidation of iron metal===
-When in contact with water and oxygen, or other strong oxidants and/or acids, iron will rust. If salt is present as, for example, in salt water, it tends to rust more quickly, as a result of the [[Electrochemistry|electro-chemical]] reactions.  Iron metal is relatively unaffected by pure water or by dry oxygen. As with other metals, a tightly adhering oxide coating, a [[passivation layer]], protects the  bulk iron from further oxidation. Thus, the conversion of the passivating iron oxide layer to rust results from the combined action of two agents, usually oxygen and water.  Other degrading solutions are [[sulfur dioxide]] in water and [[carbon dioxide]] in water.  Under these corrosive conditions, iron(III) species are formed.  Unlike iron(II) oxides, iron(III) oxides are not passivating because these materials do not adhere to the bulk metal.  As these iron(III) compounds form and flake off from the surface, fresh iron is exposed, and the corrosion process continues until all of the iron(0) is either consumed or all of the oxygen, water, carbon dioxide, or sulfur dioxide in the system are removed or consumed. <ref>Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.</ref>
-===Chemical reactions associated with rusting===
-The rusting of iron is an [[electrochemistry|electrochemical]] process that begins with the transfer of [[electrons]] from iron to [[oxygen]].<ref>Hubert Gräfen, Elmar-Manfred Horn, Hartmut Schlecker, Helmut Schindler "Corrosion" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH: Weinheim, 2002. DOI: 10.1002/14356007.b01_08</ref>  The rate of corrosion is affected by water and accelerated by [[electrolyte]]s, as illustrated by the effects of road salt on the corrosion of automobiles.  The key reaction is the reduction of oxygen:
-:O<sub>2</sub>  +  4 e<sup>-</sup>  +  2 H<sub>2</sub>O   →   4 OH<sup>-</sup>
-Because it forms [[hydroxide]] [[ions]], this process is strongly affected by the presence of acid.  Indeed, the [[corrosion]] of most metals by oxygen is accelerated at low [[pH]].  Providing the electrons for the above reaction is the oxidation of iron that may be described as follows:
-:Fe  →  Fe<sup>2+</sup>  +  2 e<sup>−</sup>
-The following redox reaction also occurs in the presence of water and is crucial to the formation of rust:
-:4 Fe<sup>2+</sup> +  O<sub>2</sub> → 4 Fe<sup>3+</sup>  + 2 O<sup>2−</sup>
-Additionally, the following multistep acid-base reactions affect the course of rust formation:
-: Fe<sup>2+</sup>  +  2 H<sub>2</sub>O  {{unicode|⇌}}  Fe(OH)<sub>2</sub>  +  2 H<sup>+</sup>
-: Fe<sup>3+</sup> +  3 H<sub>2</sub>O {{unicode|⇌}} Fe(OH)<sub>3</sub>  +  3 H<sup>+</sup>
-as do the following dehydration equilibria:
-:Fe(OH)<sub>2</sub> {{unicode|⇌}}  FeO + H<sub>2</sub>O
-:Fe(OH)<sub>3</sub> {{unicode|⇌}}  FeO(OH) + H<sub>2</sub>O
-:2 FeO(OH) {{unicode|⇌}}  Fe<sub>2</sub>O<sub>3</sub> + H<sub>2</sub>O
-From the above equations, it is also seen that the corrosion products are dictated by  the availability of water and oxygen.  With limited dissolved oxygen, iron(II)-containing materials are favoured, including [[iron(II) oxide|FeO]] and black [[lodestone]] (Fe<sub>3</sub>O<sub>4</sub>).  High oxygen concentrations favour [[ferric]] materials with the nominal formulae Fe(OH)<sub>3-x</sub>O<sub>x/2</sub>. The nature of rust changes with time, reflecting the slow rates of the  reactions of solids.
-Furthermore, these complex processes are affected by the presence of other ions, such as [[calcium|Ca<sup>2+</sup>]], which both serve as an electrolyte, and thus accelerate rust formation, or combine with the [[hydroxides]] and [[oxides]] of iron to precipitate a variety of Ca-Fe-O-OH species.
-===Water cleaning===
-[[Nanoparticles]] of rust have been shown to be effective at cheaply removing [[arsenic]] from water sources to help make them safe to drink. <ref>http://www.guardian.co.uk/science/2006/nov/10/water.environment</ref>
-==Rust prevention==
-:''Main article: [[Rustproofing]]''
-Rust is permeable to air and water, therefore the interior iron continues to corrode. Rust prevention thus requires coatings that preclude rust formation.  [[Stainless steel]] forms a passivation layer of [[chromium(III) oxide]]. Similar passivation behavior occurs with [[magnesium]], [[titanium]], [[zinc]], aluminium.
-An important approach to rust prevention entails [[galvanization]], which typically consists of an application, on the object to be protected, of a layer of zinc by either [[hot-dip galvanizing]] or [[electroplating]].  Zinc is traditionally used because it is cheap, adheres well to steel and provides a cathodic protection to the steel surface in case of damage of the Zinc layer. In more corrosive environments (such as salt water) [[cadmium]] is preferred. Galvanization often fails at seams, holes, and joints, where the coating is pierced. In these cases the coating provides [[cathodic protection]] to metal, where it acts as a [[galvanic anode]] rusting in preference.  More modern coatings add aluminium to the coating as ''zinc-alume'', aluminium will migrate to cover scratches and thus provide protection for longer. These approaches rely on the aluminium and zinc oxides protecting the once-scratched surface rather than oxidizing as a [[sacrificial anode]].
-In some cases, very aggressive environments or long design life, both zinc and a [[coating]] are applied to provide corrosion protection.
-Several other methods are available to control corrosion and prevent the formation of rust, colloquially termed [[rustproofing]]:
-*[[Cathodic protection]] is a technique used to inhibit corrosion on buried or immersed structures by supplying an electrical charge that suppresses the electrochemical reaction. If correctly applied, corrosion can be stopped completely. In its simplest form it is achieved by attaching a sacrificial anode thus making the iron or steel the cathode in the cell formed. The sacrificial anode must be made from something with a more negative [[electrode potential]] than the iron or steel, commonly zinc, aluminium or magnesium.
-*[[Bluing (steel)|Bluing]] is a technique that can provide limited resistance to rusting for small steel items, such as firearms; for it to be successful, water-displacing oil is rubbed onto the blued steel.
-*Rust formation can be controlled with [[coating]]s, such as [[paint]], that isolate the iron from the environment. Large structures with enclosed box sections, such as ships and modern automobiles, often have a wax-based product (technically a "slushing oil") injected into these sections. Such treatments also contain rust inhibitors. Covering steel with concrete provides protection to steel by the high pH environment at the steel-concrete interface.
-*Another method to avoid rust is to control the environment. Controlling the humidity, if possible, below a certain thereshold can reduce or stop the corrosion process.
-*Rusting can be controlled also by proper design, avoiding for example areas of stagnant water, galvanic coupling with more noble materials.
-*Corrosion inhibitors, like gas phase or volatile inhibitors can be used to prevent corrosion in closed systems.
-*A simple and inexpensive way to remove rust from [[steel]] surfaces by hand is to rub the steel with [[aluminium foil]] dipped in water.  Aluminium has a higher [[reduction potential]] than the [[iron]] in [[steel]], which may help transfer [[oxygen]] atoms from the iron to the aluminium.  The aluminium foil is softer than steel and will not scratch it, as [[steel wool]] will, but as the aluminium oxidizes, the [[aluminium oxide]] produced becomes a fine [[metal polishing]] compound. <ref>{{cite book | last = Stoughton | first = Bradley| authorlink = Bradley Stoughton| title = The metallurgy of iron and steel| publisher = Hill Publishing Co.| date = 1908| location = New York| pages = 476| url = http://www.archive.org/details/metallurgyofiron00stourich | year= 1908}}</ref>
-==Economic impact==
-{{Main|Corrosion}}
-[[Image:Silver Bridge collapsed, Ohio side.jpg|thumb|right|The collapsed Silver Bridge, as seen from the Ohio side]]
-Rust is associated with degradation of iron-based tools and structures.  As rust has a much higher volume than the originating mass of iron, its build-up can also cause failure by forcing apart adjacent parts — a phenomenon sometimes known as "rust smacking". It was the cause of the collapse of the [[Mianus river bridge]] in 1983, when the bearings rusted internally and pushed one corner of the road slab off its support. Rust was also an important factor in the [[Silver Bridge (bridge)|Silver Bridge]] disaster of 1967 in [[West Virginia]], when a steel [[suspension bridge]] collapsed in less than a minute, killing 46 drivers and passengers on the bridge at the time.
-[[Image:Collapsed Kinzua Bridge.jpg|250px|thumb|left|The [[Kinzua Bridge]] after it collapsed]]
-[[Kinzua Bridge]] in [[Pennsylvania]] was blown down by a [[tornado]] in 2003 largely because the central base bolts holding the structure to the ground had rusted away, leaving the bridge resting by gravity alone.
-Similarly corrosion of concrete-covered steel and iron can cause the concrete to [[spall]], creating severe structural problems. It is one of the most common failure modes of [[reinforced concrete]] [[bridge]]s.
-==See also==
-*[[Cosmoline]]
-*[[List of bridge disasters]]
-*[[Tetanus#Association with rust | Relevance to Tetanus]]
-*[[Rustproof iron]]
-*[[Weathering steel]]
-*[[WD-40]]
-==References==
-{{reflist}}
-==External links==
-{{commons|Rust}}
-*[http://www.corrosioncost.com Corrosion Cost] A site dedicated to the study of economic impact of Corrosion
-*[http://openlearn.open.ac.uk/mod/resource/view.php?id=233628 corrosion case studies] Analysis of corrosion
-*[http://www.corrosion-doctors.org/MatSelect/corrsteel.htm Corrosion Doctors] Rusting article
-*[http://www.corrosionist.com/how_does_rust_form.htm Metal Corrosion Rust] What is Rust
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