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Homework Help: Reaction of AgNO3, CaCl2, and Al2(SO4)3 with Ba(NO3)2 and then NaCl?

  1. Aug 29, 2010 #1
    1. The question is as follows: "You know that unlabeled bottle contains one of the following: AgNO3, CaCl2, or Al2(SO4)3. A friend suggests that you test a portion of the bottle with Ba(NO2)3 and then with NaCl. What behavior would you expect when each of these compounds is added to the unlabeled bottle?"


    a) AgNO3(aq) + Ba(NO2)3 (s) = AgNO3 (aq) + Ba(NO2)3 (aq)

    b) CaCl2 (aq) + Ba(NO2)3 (s) = BaCl2 (aq) + Ca(NO3)2 (aq)

    c) Al2(SO4)3 (aq) + 3Ba(NO2)3 (s) = 3BaSO4 (s) + 2Al(NO3)3 (aq)

    However, where I am stuck is figuring out how NaCl (s) reacts with the products of those three reactions. I'm aware that the first will produce AgCl as a precipitate and the second will not produce a precipitate, but I'm finding it difficult to figure out and balance the equations with three reactants. My tries are below, but I feel as if I am doing something wrong. Any help is greatly appreciated! I'm tearing my hair out! :P


    a) AgNO3 + Ba(NO3)2 + NaCl = NaNO3 + AgCl + BaCl2 (do I list Ba(NO3)2 and AgNO3 again as the ions can recombine?)

    b) BaCl2 + Ca(NO3)2 + NaCl = NaCl + BaCl2 + NaNO3 + CaCl2

    c) BaSO4 (s) + Al(NO3)3 + NaCl = Na2SO4 + NaNO3+ BaCl2 + AlCl3
    Last edited: Aug 30, 2010
  2. jcsd
  3. Aug 30, 2010 #2


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    Staff: Mentor

    As I understand the question it is not adding the second reagent to the mixture, but splitting the mixture into two parts and testing each part separately.

    Add state information (as (s), (aq)) to your reaction equations, they will be easy to follow both for you and us.

    Do you know what a net ionic reaction is? If so, try to rewrite the reactions as net ionic.
    Last edited by a moderator: Aug 13, 2013
  4. Aug 30, 2010 #3
    Sorry about the lack of state information; I was in a bit of a rush and in a state of upset. I've added them now.

    Do you think so? I thought the phrase "you test a portion of the bottle with Ba(NO3)2 and then with NaCl" indicates that you add NaCl to the same sample right after the Ba(NO3)2 (s) ? It also says "What behavior would you expect when each of these compounds is added to the unlabeled bottle," so I'm assuming there's only one unlabeled bottle to which you're adding these two compounds? Please correct me if I'm wrong. :)

    I do know how to write a net ionic equation, and I would have had I not run into this problem :P.

    I can write them out for the first step, yes, but since I'm confused with the addition of NaCl (s), I can't write those out yet.

    a) No net ionic - no reaction

    b) No net ionic - no reaction

    c) 3SO42- (aq) + 3Ba2+ (aq) = 3BSO4 (s)

    I know you said that you think that the Ba(NO3)2 (s) and the NaCl (s) are added separately, but is it possible to add the NaCl (s) right after the Ba(NO3)2 (s) and have a reaction with all those ions floating around (especially in reactions a and b). I hope I'm not being too confusing or vague.

    I really appreciate your help! :)
  5. Aug 30, 2010 #4


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    Staff: Mentor

    OK, perhaps I am misreading the question - it is a little bit ambiguous to me, but then English is my second language.

    Assuming you have to add both salts to the same sample - think what ions are present in the mixture. It really isn't much harder than mixing two salts, you just look what ions are present and what can happen. So far you are right with Ba(NO3)2 - a & b no reaction, c precipitation of solid.
    Last edited by a moderator: Aug 13, 2013
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