Register - Log In

FunTrivia Homepage

  • New Questions

  • Unanswered

  • Post a Question
  • Goto Qn #


    How does water make metals oxidize?

    Question #64979. Asked by tjoebigham. (Apr 24 06 2:09 PM)


    Air-free water has little effect upon iron metal. However, iron metal reacts in moist air by oxidation to give a hydrated iron oxide. This does not protect the iron surface to further reaction since it flakes off, exposing more iron metal to oxidation. This process is called rusting and is familiar to any car owner.


    Apr 24 06, 5:45 PM

    When steel contacts water, an electrochemical process starts. On the surface of the metal, iron is oxidised to iron(II):

    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:

    4e- + O2 + 2H2O → 4OH-

    The hydroxide ions react with the iron(II) ions and more dissolved oxygen to form iron oxide. The hydration is variable, however in its most general form:

    Fe2+ + 2OH- → Fe(OH)2


    Hence, rust is hydrated iron(III) oxide. Corrosion tends to progress faster in seawater than fresh water due to higher concentration of sodium chloride ions, making the solution more conductive. Rusting is also accelerated in the presence of acids, but inhibited by alkalis. Rust can often be removed through electrolysis, however the base metal object can not be restored through this method.



    Apr 24 06, 9:54 PM


    Sign up to see all responses!


    Choose a User Name:
    Your Email Address:
    Choose a Password:

    I agree by the terms outlined in FunTrivia's Conditions of Use

    Other Similar Questions & Answers

    What difference does the water temperature make in washing clothes, usually when I go to the laundromat and hit color clothes, I get warm water, but recently, only cold water came out, does that matter?

    Penguins spend a good part of their lives in the water as well as on land. As they have been known to achieve speeds of up to 90 kph in the water, does that make them the fastest amphibian?

    Is there any metal on earth that doesn't oxidize (rust or tarnish)?

    Suggested Related FunTrivia Quizzes - 90,000 currently online

    1 The World of Metals!
    Many of our everyday appliances are made of metals. This quiz will test your knowledge about them.
    Metals Tough
    10 Q
    Apr 22 07
    2577 plays
    2 Precious Metals
    We all love shiny stuff! Gold, platinum, silver, and palladium are classed as precious metals. How much do you know about this small collection of very valuable elements?
    Metals Tough
    10 Q
    Oct 31 10
    516 plays
    3 Water, Water!
    These questions are on the various bodies of water in the world.
    Bodies of Water Tough
    10 Q
    May 05 01
    2592 plays
