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Precipitation reactions and all that sh*t... (1 Viewer)

morganforrest

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Chemistry Syllabus said:
Deduce the ions present in a sample from the results of tests
But which ones?

I know carbonate, chloride, phosphate, sulfate, lead (II), Copper, Calcium and Barium

Any others I should know?
 

mzduxx2006

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morganforrest said:
But which ones?

I know carbonate, chloride, phosphate, sulfate, lead (II), Copper, Calcium and Barium

Any others I should know?
ur such a stooge. u had all year to learn this shyt and u decide to recite it the night before?

test for cations

add chloride if a white precipitate occurs then Pb is present. if no reaction than SO4 is added and if a white precipitate occurs then this indicates that Ba + Ca are present(which will further be determined by flame tests) if no results are identified then OH is added and a blue precipitate identifies copper, brown precipitate indicates iron 3+ with green precipitate turning brown identifying iron 2+.

Test for anions.

An acid is added, if bubbles appear then carbonate (CO3) is present. If no reaction is seen then barium is added, a white precipitate will indicate SO4, if no result is identified then Ag is added, a white precipitate which darkens in sunlight will identify chloride. If no reaction is seen then iron is added, a green precipitate will identify PO3.<!-- google_ad_section_end -->
 

morganforrest

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Ur shit...I do know them, I was asking if there was any other ions I should know as the syllabus doesn't specifiy which types, though past HSC's have asked for specific ions
 

joelfh1

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... we have to remember that whole damn flow chart?:bomb:
 

nat_doc

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its not hard to remember... got me 5 easy marks in my exam:D
 

joelfh1

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it seems ok on paper but for some reason, its the hardest part of the course so far for me.

I think i'll have to drill it so i can learn by rote...
 

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