Solubility (1 Viewer)

Counterfeit

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Fuck.

Solubility rules have been plaguing me since the early days of year 11... I just don't understand.

I can't get my head around them.

I know they rules, and i know cation and anion tests but I just can't apply them!

They never ever seem to work, like i always seem to encounter questions where a nitrate forms a ppt? WTF! thats impossible no?

Anyway here's a couple questions i would love somebody to have a look at and explain, They SHOULD be simple, I have the answers, but they dont help, all they tell me is i got it wrong.



Which Results conclude that Pb 2+ is present? (from "table" below)

Anion= CHLORIDE ADDED SULFATE ADDED CARBONATE ADDED
Cation A) no ppt no ppt ppt
B) ppt ppt no ppt
C) ppt ppt ppt
D) no ppt ppt no ppt



NEXT QUESTION:

Mixture of anions P Q R (add Zn(NO3)2) ===> White ppt (H) (add HCl) ===> Bubbles of colourless gas (K)

Identify H and K

:S:S help
 

like_ma_style

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First question: C. I think. lol

Yeah i thought a nitrate precipitate wasn't possible.
 

serge

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like_ma_style said:
First question: C. I think. lol

Yeah i thought a nitrate precipitate wasn't possible.
yeh, same, plus its not in the syllabus so dont worry about it

colourless gas probably means there's a carbonate in there
 

Counterfeit

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serge said:
yeh, same, plus its not in the syllabus so dont worry about it

colourless gas probably means there's a carbonate in there
not in the syllabus? solubilty rules... and its a past HSC paper so it must be in the syllabus :)

why C? (like i said, i don't understand!)
 

serge

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Counterfeit said:
not in the syllabus? solubilty rules... and its a past HSC paper so it must be in the syllabus :)

why C? (like i said, i don't understand!)


"perform first-hand investigations to carry out a range of tests, including flame tests, to identify the following ions:
phosphate
sulfate
carbonate
chloride
barium
calcium
lead
copper
iron"

I didnt say it was C i think its B

nitrates dont form precipitates, and we dont need to find Zinc precipitates
either, so its probably an old HSC paper from the older syllabus
 
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