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GChem - Help me balance this equation?

Discussion in 'DAT Discussions' started by roxie2love, Dec 27, 2008.

  1. roxie2love

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    I can't seem to balance this equation properly, any help is appreciated! Thanks in advance!

    KMnO_4 + NH_3 -> KNO_3 + MnO_2 + KOH + H_2_O



    Answer : 8KMnO_4 + 3NH_3 -> 3KNO_3 + 8MnO_2 + 5KOH + 2H_2_O
     
    #1 roxie2love, Dec 27, 2008
    Last edited: Dec 28, 2008
  2. doc3232

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    That's tough. IMO, it is rather time consuming also. I don't think it would be on the test.
     
  3. Danny289

    Danny289 Member
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    KMno4=======> Mno2
    Mn+7 +3e=======> Mn+4 3=reduction
    -----------------------------------------------
    NH3=======> KNO3
    N-3 ======> N+5 +8e 8= oxidation
    now switch 8 and 3 in your equation and....
    ------------------------------
    recall from G chem
    Kmno4 ==> finding oxide number for Mn ==> 1+ X +(-2. 4)=0===> X=+7
    for NH3===> finding for N===> X+3=0 ===> X= -3 and......................
     
  4. kmk0984

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    Isn't it suppose 8MnO2 in the product?
    Thanks
     
  5. Danny289

    Danny289 Member
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    yes must be 8Mno2
     
  6. roxie2love

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    Thanks for noticing that - I fixed it now, it should read 8MnO_2. :thumbup:
     

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