Identifying ions in solution using precipitation reactions

[Joules23]

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: ______

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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: _______

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Anyone have any idea as to how i would find this out, without actually performing the experiment?

 

[NotMrX]

This link might help

http://en.wikipedia.org/wiki/Solubility_chart

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

Look what for what is insoluble with the new ions from the stuff you add

 

[cheechnchong]

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...

 

[Joules23]

i still don't 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?

 

[Joules23]

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?"

 

[lightarrow]

AgCl, AgBr and BaSO4 are insoluble; every other combination is soluble...

 

[Joules23]

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

 

[lightarrow]

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 ?

#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.

 

[Stevedye56]

When you use the solubility chart the higher always prevails, is that where your getting caught?