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Writing net ionic equations and predict precipitate.

lil_killer129lil_killer129 Posts: 4,706Registered User Senior Member
edited October 2006 in AP Tests Preparation
4. Write the net ionic equations for the reation, if any, that occurs when aqueous solutions of the following are mixed.



f. silver nitrate and ammonium carbonate
How do I do this?



g. strontium nitrate and potassium iodide
Sr2+ (aq) + I- (aq) ---> SrI2 (s)
Is this right?


3. Find the precipitates, if any.

e. Hg2(NO3)3 (aq) + CuSO4 (aq)
>

f. Ni(NO3)2 (aq) + CaCl2 (aq)
>
No precipitate. Is this right?


g. K2CO3 (aq) + MgI2 (aq)
>
Precipitate formed: KI
Is this right?


h. Na2CrO4 (aq) + AlBr3 (aq)
>


I am really bad at predicting products and finding the precipitates. Can someone look over these and help me out? I have a quiz on Tuesday on this. AHHHH...
Post edited by lil_killer129 on

Replies to: Writing net ionic equations and predict precipitate.

  • Gyros321Gyros321 Posts: 1,842Registered User Senior Member
    Ok for E F G and H I may be totally wrong... but
    in E. shouldn't HGso4 be a precip? I remember So4 is sol in a lot of things but I don't think it is in HG.
    In f. i think ur right
    G. Woah Woah Woah. You really need to know I BR and CL are sol in almost everything. Also group 1 metals are also sol in almost anything. however MgCo3 is not sol.
    For h. i think its none (not sure)
    I got a 5 on the ap chem.. i remember solubility still pretty well.
  • lil_killer129lil_killer129 Posts: 4,706Registered User Senior Member
    Thanks Gyros321. Can anyone else offer me any help? I really want to ace this quiz on Tuesday.
  • candace9930candace9930 Posts: 84Registered User Junior Member
    hum .. I dont know how I can help you but since we are learning the same thing right now i could give you some advice. When you are predicting if the reaction is a preciptation, you have to know the solubility rule. If an element is insoluble then yuou will have a preciptation reaction cuz it will turn solid. And remembers IONS have to be involved in order to preciptate. Therefore its important to look for the ions first, if no ions, then you can tell that its not gonna be a preciptation. Two nonmetals .. no precipation. (thats all I can remember so far.. )
  • LuckMC11LuckMC11 Posts: 807Registered User Member
    lol, we're doing the same thing 2
  • amismartenoughamismartenough Posts: 99Registered User Junior Member
    f. silver nitrate and ammonium carbonate

    Ag2+ + CO3 2- => AgCO3


    g. strontium nitrate and potassium iodide
    Sr2+ (aq) + I- (aq) ---> SrI2 (s)
    Is this right?

    I think it's:

    I- => I2 (g)


    h. Na2CrO4 (aq) + AlBr3 (aq)
    >

    precipitate is Al2CrO43


    btw...I got a 5 on the AP, so hopefully i have some credibility :)
  • chickenboi8008chickenboi8008 Posts: 2,500Registered User Senior Member
    u really have to know ur solubilities. i just learned this stuff yesterday but it is very straightforward. and know ur charges of each ions. remember, always switch the positive and negative ions of each compound and then rewrite the new compounds. then remember see which is soluble and if they both are, then there is no reactant.
  • LongdaysaheadLongdaysahead Posts: 327Registered User Junior Member
    nitrate is always soluble
    acetate is always soluble
    all chlorides/bromides/iodides are soluble except with silver,mercury lead
    sulfate is always soluble except with strontium,barium,mercury,lead

    hydroxides/sulfides are always insoluble except with group 1a metal cations, ammonium, and strontium barium calcium
    phosphate/carbonate are always insoluble except with group 1a metal cations and ammonium
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