Chem

posted by .

How would one balance the following redox reaction using the half reaction method?

Fe(OH)2 + O2 + H2O ---> Fe(OH)3

This is in my chemistry teacher's homework, and it comes up with an answer, but I don't see how to use the half reaction method when there is only one substance on the right side. Please help. Thank you very much.

  • Chem -

    4Fe(OH)2 + O2 + 2H2O ==> 4Fe(OH)3

    Stepwise: Balanced half cell for Fe is
    equn 1 is Fe^2+ ==> Fe^3+ + e

    O2 ==> 2OH^-
    O2 changes from zero to -4 on the right. Add 4e to the left side.
    O2 + 4e ==> 2OH^-
    Count up the charge. -4 on the left and -2 on the right. Add 2OH^- on the right to balance which makes it
    O2 + 4e ==> 4OH^-. Now add water to balance the H which makes it
    equn 2 balanced half cell is O2 + 4e + 2H2O ==> 4OH^-

    Multiply equn 1 by 4 and equan 2 by 1 and add the two.
    4Fe^2+ O2 + 2H2O ==> 4OH^- + 4Fe^3+
    Add 8OH^- on the left and right.
    4Fe(OH)2 + O2 + 2H2O --> 12OH^- + 4Fe^3+
    4Fe(OH)2 + O2 + 2H2O ==> Fe(OH)3
    Voila.

  • Chem--typo last line -

    4Fe(OH)2 + O2 + 2H2O ==> 4Fe(OH)3

    Stepwise: Balanced half cell for Fe is
    equn 1 is Fe^2+ ==> Fe^3+ + e

    O2 ==> 2OH^-
    O2 changes from zero to -4 on the right. Add 4e to the left side.
    O2 + 4e ==> 2OH^-
    Count up the charge. -4 on the left and -2 on the right. Add 2OH^- on the right to balance which makes it
    O2 + 4e ==> 4OH^-. Now add water to balance the H which makes it
    equn 2 balanced half cell is O2 + 4e + 2H2O ==> 4OH^-

    Multiply equn 1 by 4 and equan 2 by 1 and add the two.
    4Fe^2+ O2 + 2H2O ==> 4OH^- + 4Fe^3+
    Add 8OH^- on the left and right.
    4Fe(OH)2 + O2 + 2H2O --> 12OH^- + 4Fe^3+
    4Fe(OH)2 + O2 + 2H2O ==> 4 Fe(OH)3

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    1) Balance this redox reaction using the oxidation-number method. Zn + O2 + HCl ® ZnCl2 + H2O 2) Balance this redox reaction using the half-reaction method. (basic solution) Zn + MnO4- ® Zn(OH)2 + MnO2
  2. Chemistry

    I know nothing about chemistry, but am wondering if someone could help me with these. 1) Balance this redox reaction using the oxidation-number method. Zn + O2 + HCl ® ZnCl2 + H2O 2) Balance this redox reaction using the half-reaction …
  3. chemistry

    Ag+HNO3-----AgNO3+NO+H2O balance the redox reaction using the oxidation-number method
  4. chemistry

    Balance the following redox reaction using the half reaction method: NaIO3+KI==> I2+H20+Na(+1)+K(+1)
  5. chemistry-balanced redox equations

    Use the following steps to balance the redox reaction below: Mg + Au+ Mg2+ + Au a. Write the oxidation and reduction half-reactions. Make sure each half-reaction is balanced for number of atoms and charge b. Multiply each half-reaction …
  6. chemistry

    Using the half-reaction method, balance the redox reaction below. Show your work; partial credit will be given. I- + Br2 → IO3- + Br- Write the reduction and oxidation half-reactions. Balance them for atoms. Balance each of the …
  7. Chem

    Balance the following redox reactions in acidic solution by the half-reaction method Br–(aq) + I–(aq) + HClO(aq) = Br2(l) + IO3 + Cl–(aq)
  8. General Chemistry

    Balance the following redox reaction in acidic and basic solutions: Fe(OH)2(s) + O2(g) --> Fe(OH)3(s) These are the steps my instructor gave us to balance redox reactions: 1. Divide into 1/2 rxns (reduction & oxidation) 2. Balance …
  9. Chemistry

    I need chemistry help. I think 1. c, 2.b, & 3.a (please tell me why or why not and help me set up the problems if possible) 1.) The following half reaction has been balanced except for the electrons. How many and where should the electrons …
  10. Chemistry

    Balance the redox reaction below using the half-reaction method. Bi3+(aq) + Co(s)Bi(s) + Co2+(aq)

More Similar Questions