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Chemistry Problem/puzzle

  1. Oct 10, 2006 #1
    1) A solution contains one or more of the following:
    Silver nitrate
    Potassium sulfate
    iron(III) nitrate
    Barium bromide

    You add one drop of hydrochloric acid (solution). There is a precipitate.

    Next you add one drop of barium nitrate (solution). There is no observable reaction.

    Present: ______
    Absent: ______
    Your next step: ______

    2) A solution contains none or some of the following:
    Silver nitrate
    Copper(II) sulfate
    iron(III) chloride
    barium nitrate

    You ad one drop of barium chloride (solution). There is no observable change.
    Next you add one drop of sodium sulfate (solution). There is no observable change.

    Present: ______
    Absent: ______
    Next step: _______


    Anyone have any idea as to how i would find this out, without actually performing the experiment?
  2. jcsd
  3. Oct 10, 2006 #2
    This link might help


    <a href="http://en.wikipedia.org/wiki/Solubility_chart">solubility [Broken] chart</a>

    Look what for what is insoluble with the new ions from the stuff you add
    Last edited by a moderator: May 2, 2017
  4. Oct 10, 2006 #3
    also remember this:

    if A Compound in water...

    is soluble = no precipitant
    insoluble = precipitant

    use the solubility chart/table to determine what is soluble/insoluble. Shouldnt be that difficult...
  5. Oct 10, 2006 #4
    i still dont understand i looked on the chart for #1 and they all are Soluble.... how would adding the HCl factor in with the chart

    HNO3 (3 is subscript)
    HSO4 (4 is subscript)
    3NO3H (2nd 3 is subscript)
    HBr2 (2 is subscript)

    Those are what i got after adding the HCl to the silver nitrate, potassium sulfate, etc... Now where do i go from there?
    Last edited: Oct 10, 2006
  6. Oct 12, 2006 #5
    ok please let me know if i got this right

    for #1, the only one present is silver nitrate

    for #2 the only ones present are Copper(II) sulfate and iron(III)chloride

    Also what is meant by, "your next step?"
  7. Oct 16, 2006 #6
    AgCl, AgBr and BaSO4 are insoluble; every other combination is soluble...
  8. Oct 18, 2006 #7
    im still not understanding it.... ok, insoluble = precipitate .. so are you saying for both #1 and #2, the ones present are AgCl, AgBr and BaSO4 ?

    btw, yes i am stupid
    Last edited: Oct 18, 2006
  9. Oct 21, 2006 #8
    #1. If you add HCl and there is a precipitate (=insoluble) and the only insoluble substance among those could be AgCl, what do you conclude? If you add Ba++ and there is no precipitate, knowing that the only insoluble substance could be BaSO4, what do you conclude? Ecc.
  10. Oct 21, 2006 #9
    When you use the solubility chart the higher always prevails, is that where your getting caught?
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