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Algebraic method to balance redox equations

  1. Oct 20, 2013 #1
    Hi all,

    I'm learning how to solve redox equations. I found the algebraic method to solve equations such as this one:
    Fe[itex]^{2+}[/itex] + Cr[itex]_{2}[/itex]O[itex]_{7}[/itex][itex]^{2-}[/itex] +H[itex]^{+}[/itex][itex]\rightarrow[/itex] Fe[itex]^{3+}[/itex] + Cr[itex]^{3+}[/itex] + H[itex]_{2}[/itex]0
    and i was able to solve it.

    What I don't see is how to use that algebraic method to solve an equation without superscripts; since it doesn't allow you to balance the charges, right?
    like for example: NaOH + Cr(OH)[itex]_{3}[/itex] + NaClO[itex]\rightarrow[/itex] Na[itex]_{2}[/itex]CrO[itex]_{4}[/itex] +NaCl + H[itex]_{2}[/itex]O

    Thanks for your help.
  2. jcsd
  3. Oct 23, 2013 #2


    User Avatar

    Staff: Mentor

    If everything is neutral (on both sides of the reaction) there is no need to separately balance the charge. But you can always write an additional identity

    [tex]0\times a_1 + 0\times a_2 + ... = 0\times b_1 + 0\times b_2 + ...[/tex]

    (assuming ai are stoichiometric coefficients on the LHS of the equation, and bi are coefficients on the RHS).

    Compare ChemBuddy lecture on the algebraic method of reaction equation balancing - it shows how to balance both equations with charged and uncharged species.

    Use [noparse] and [/noparse] tags to format the formulas, don't mix normal text with LaTeX, it is not guaranteed to work OK.
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