Iron Corrosion (Rusting)

4Fe + 3O2 + 6H2O → 4Fe(OH)3

Visão geral

Iron corrosion is an electrochemical process where iron is oxidized to Fe²⁺/Fe³⁺ at anodic sites while oxygen is reduced at cathodic sites. The process requires both water and oxygen. The initial Fe(OH)₂ product is further oxidized to Fe(OH)₃, which dehydrates to form rust (Fe₂O₃·nH₂O).

Participantes

Papel Substância Coeficiente Estado
Reagente Oxygen O 3 (g)
Reagente Iron Fe 4 (s)
Reagente Water H₂O 6 (l)

Exemplo do cotidiano

A car's body rusting over time, iron nails turning orange-brown, and bridge structures corroding all involve this electrochemical process.

Importância industrial

A corrosão custa à economia global mais de 2,5 biliões de euros anuais. Compreender e prevenir a corrosão é crítico para a engenharia civil, os transportes e as infraestruturas. A galvanização, a pintura e os ânodos de sacrifício são soluções comuns.

Propriedades

Tipo
Redox
Reversível
Não
Energia
Exotérmico
ΔH
-1648,0 kJ/mol

Reações relacionadas

Iron(II) to Iron(III) Oxidation by Oxygen Bleaching with Sodium Hypochlorite Copper Reduction of Silver Ion Aqua Regia Dissolving Gold Cerium(IV) Reduction by Iron(II) Chlorine Oxidation of Bromide Copper Oxidation by Nitric Acid Hypochlorite Oxidation of Hydrogen Peroxide Hydrogen Peroxide as Oxidizing Agent (Acidic) Displacement of Hydrogen from Acid by Magnesium

Frequently Asked Questions

What is the equation for Iron Corrosion (Rusting)?
The balanced equation is: 4Fe + 3O₂ + 6H₂O → 4Fe(OH)₃.
What type of reaction is Iron Corrosion (Rusting)?
Iron Corrosion (Rusting) is a redox reaction.
Is Iron Corrosion (Rusting) exothermic or endothermic?
Iron Corrosion (Rusting) is exothermic (releases energy). The enthalpy change (ΔH) is -1648.0 kJ/mol.