Chemical equilibrium system and where my ions went

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allywallyrus
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sorry if this has been asked before, i did a search and couldn't find any results.
Explain fully what happens when [tex]H^+[/tex] is added to a mixture containing [tex]BaCrO_4(s)[/tex] and [tex]CrO_4^2^-[/tex].

The overall equation of ions in this experiment is [tex]H^+(aq)~+~2CrO_4^2^-\rightleftharpoons~Cr_2O_7^2^-(aq)~+~OH^-(aq)[/tex]

when HCl is added to a solution of K2CrO4 and NaOH and Ba(NO3)2, the precipitate dissolves and the solution becomes orange. I am pretty stumped, but I am assuming K2CrO7 is present because it is orange in colour and that the precipitate from before becomes aqueous again but I am not sure what the percipitate is (possibly Ba(OH)2??) or what is involved in the reaction. any push in the right direction is very appreciated!
 
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Ksp of barium hydroxide is 5 X 10-3 and the Ksp of barium chromate is 2.2 X 10-10.

Hope it helps.
 
chemisttree said:
Ksp of barium hydroxide is 5 X 10-3 and the Ksp of barium chromate is 2.2 X 10-10.

Hope it helps.

i just realized i even identified barium chromate as a solid in my first post, hahaha :P
thank you anyway

so now my equation is looking more like HCl(aq) + BaCrO4 -> Cr2O7 + BaCl(aq) + H+
 
allywallyrus said:
[tex]H^+(aq)~+~2CrO_4^2^-\rightleftharpoons~Cr_2O_7^2^-(aq)~+~OH^-(aq)[/tex]

It won't work this way. Think what will happen to produced OH- in the presence of H+.
 
Borek said:
It won't work this way. Think what will happen to produced OH- in the presence of H+.

so we'd have H2O in the products instead, which makes more sense because this also balances nicely as well
i think this clears up where H+ ions were going, thanks :)

i don't suppose it would be a problem if i recycled this thread for questions on the same subject? i will probably have some more
 
No, you better start a new thread. Give it more informative subject.