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Homework Help: Writing Equations

  1. Jul 24, 2008 #1
    1. The problem statement, all variables and given/known data
    Write a balanced equation and indicate the reaction type (single/double replacement, decomposition, or synthesis) for each of the following:
    a) Sulfuric acid (aq) + potassium hydroxide (aq) -->

    b) Zinc (s) + sulfuric acid (aq) -->

    2. Relevant equations



    3. The attempt at a solution

    a) H2SO4 (aq) + KOH (aq) --> K2S (aq) + H2O (L) (double replacement) -- can't seem to balance it though...

    b) 4Zn (s) + H2SO4 (aq) --> 4ZnO (s) + H2S (aq) (single replacement)

    -- I don't know how to determine whether the products will be s, aq, or L; can someone please explain how to determine that?
     
  2. jcsd
  3. Jul 24, 2008 #2

    Borek

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    SO42- is a verrry stable group.
     
  4. Jul 25, 2008 #3

    chemisttree

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    These two examples are not oxidation/reduction reactions so there is no S-2 in the products.
     
  5. Jul 25, 2008 #4

    Borek

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    Sorry, but technically speaking second one is a redox reaction. Still, no S2- in the products.
     
  6. Jul 25, 2008 #5

    chemisttree

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    Yes, I meant that the SO4 to S-2 redox of course.
     
  7. Jul 30, 2008 #6
    How about this:
    a) H2SO4 (aq) + 2KOH (aq) --> K2SO4 (aq) + 2H2O (L) -- double replacement

    b) Zn (s) + H2SO4 (aq) --> ZnSO4 (s) + H2 (g) -- single replacement
     
  8. Jul 30, 2008 #7

    Borek

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    More or less OK. I mean - reactants and products are OK, and they are properly balanced. First reaction can be called neutralization. In the second - I would rather assume the zinc sulfate is dissolved after reaction, so more like (aq) then (s).
     
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