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Testing for Ions Confusion

I have to make a plan to test for 9 ionic compounds:
- potassium iodide, potassium chloride, potassium bromide
- potassium sulfate, potassium hydroxide, potassium carbonate
- ammonium chloride, barium chloride, magnesium chloride

I think for the iodide/chloride/bromide ions, you would do the halide test w nitric acid and silver nitrate solution, but that might also be difficult to see.

Would you do halogen displacements instead for that reason?
you are right, it might be difficult to distinguish between the silver halide precipitates. is there something you could add to the precipitates?

Spoiler



(possibly other ways as well)


what are you thinking for the other compounds?
Reply 2
Original post by bl0bf1sh
you are right, it might be difficult to distinguish between the silver halide precipitates. is there something you could add to the precipitates?

Spoiler



(possibly other ways as well)


what are you thinking for the other compounds?

i've read about adding ammonia solution, with the solubility of halide ions in dilute/conc. amminia solution allowing for the precipitate to be confirmed.

would i include halogen displacement reactions for testing these ions or test the precipitates?


For the other ions:

to test for sulfate ions, you would add HCl to remove carbonate ions and BaCl solution. if there is a white ppt, sulfate ions were present in the sample

for hydroxide ions, you would just use some sort of ph indicator, with a high ph/blue colour meaning OH- ions are present

and for carbonates, you would add some dilute HCl and it should produce CO2 if carbonate ions were present (CO2 can be tested if lime water turns cloudy when the gas is bubbled into it)

Would you also do tests for the prefixes of each ionic compound? ie would you do a flame test for potasssium and barium?
halogen displacement reactions would work as well :smile:

what have you been taught about? and what level are you studying at?

for the tests, do you have 3 sets of 3 compounds, or 1 set of all 9 compounds?
Hey sorry to start this thread again but plz help I have no clue what to do
what are you stuck with?
6E0FA163-3C8C-465F-B0BA-123AFE8C5CF1.jpg.jpeg
Where do I even start it coz I feel like if I do one the others can't be ruled out u know
can you put the compounds into groups?
try these links they might help get you started:
for halides ion : https://science-revision.co.uk/A_level_halide_ions_tests.html
sulfates and carbonates : https://science-revision.co.uk/testing%20for%20anions.html
could you use the fact that transition metal ions with 2+ and 3+ charges give coloured precipitates with hydroxide ions or that aluminium and calcium give colourless precipitates with hydroxide ions as a test for the hydroxide ion? I am not 100% sure maybe someone else can add more. The link below gives some details as well as a test for ammonium ions
https://science-revision.co.uk/test%20for%20cations.html

could you se flame tests to detect the metals present? They all seem to be nearly all potassium salts. with only barium as the other metal present. Magnesium does not give a flame colour tho!
try searching on chemguide.co.uk as well for more info
U know for kso4 do u use k instead of barium
Here it says to test with litmus but what's the point if they're all red like how will You differentiate
Is this order ok
Kco3
Kso4
Halides (KCL, KBR, KI)
Nh3cl
BaCl & mgcl
Koh last one so no test
I am sorry I dont understand your post? Is it for me or someone else?
Anyone I did it in that order, is that ok or is it wrong
8FB1674B-F4D9-4C93-9795-11D28FC1CDB3.jpg.jpeg38E6AFBA-B0E0-487E-BBD3-1A32689CA91D.jpg.jpeg
Why do CO3 then SO4 then halie

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