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What is the chemical formula of rust and its chemical name?

Dave Howe  Follow

Assuming that you mean iron or steel wire:

In the presence of both air and water (humid air), the reaction for rusting of iron is somewhat complicated:

4Fe + 3H2O(l) + 3O2(g) = Fe2O3•H2O + FeO•OH + Fe(OH)3

Change in Free Energy: ΔG(20C) = -1461.5kJ (negative, so the reaction runs)

Change in Enthalpy: ΔH(20C) = -1652.0kJ (negative, so the reaction is exothermic)

The “red rust” that you see is the Fe2O3

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Declining USA  Follow

Yes, it is the oxidation of iron.

http://en.wikipedia.org/wiki/Rust#Chemical_reactions

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Angela Aldas  Follow

Gradual decay of metal due to oxidation in presence of air and moisture.

Decay of iron in this phenomenon is called rust

Rust if Fe2O3. x H2O

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Alice Twain  Follow

Fe3 (Iron(III) is often called rust and it is acidic in nature. Chemists consider rust to be an ill-defined material which is described as hydrated ferric oxide.

When alkali is added to Iron(III) a red precipitate is formed which is then named Fe2O3-H2O also written as Fe(O)OH).

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Catherine Salierno  Follow

Hi,

I guess this question was asked regarding the general rust

Well, rust is a chemical reaction of iron when it came into physical contact with water and air over a period of time.

So, finally is a chemical reaction occurred over time due to physical contact of a metal(iron)

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Dennis Sardella  Follow

Oxidation. Or corrosion

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Badi DukviL  Follow

Because it is a chemical reaction, 4Fe + 3O2 -> 2Fe2O3

Rust is just the “historic” name, and we tend to try and remember / reference / honor the history.

The historic name of the allotrope of oxygen with 3 atoms of oxygen (ozone) is named for the fact it smelled.

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Amaury Fernandez  Follow

Rust is hydrated iron(III) oxide. Its chemical formula is usually written as Fe2O3.nH2O.

Iron(III) oxide is also known as ferric oxide.

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Charles Zellstines  Follow

Rusting is a chemical change because the iron is changed into a new substance. Changes that involve a change of state like melting ice into water and refreezing the water into ice is a physical change because at all times the only substance present was water (H2O). Rusting is a chemical change because you start with iron and end up with iron oxide, two different substances.

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