24i dont htink ur calculation is rite..
A saturated soln of H2S is 0.1M HCl at 25C contains S2- concentration of 10-23 M.The solublity product of CuS and CdS are 10-44 and 10-25.If 0.01 M solns of salts in 0.1M HCl are saturated with H2S,which will be precipitated?
Ans given is bot hCuS and CdS
but it should be CuS only naa ????????
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13Ionic Product of the salts = [0.01][10-23+0.01] > 10-25
So, Ionic product exceeds solubility product fr both, hence they both will precipitate.
106when doing calc... i got one of the ionic products as equal to its Ksp..
so isme ppt banega ya nahiin?? (of course ppt will be der... but acc to question, will more get precipitated??)
24@asish
ya in one case Q=Ksp..so it will be only saturated soln na ?
"" but acc to question, will more get precipitated?""
where is this written in ques ?
106arey complete solution cant take place..
some amount of undissolved (or ppted) solid will always remain
24we are not thinking practically...............
theoritically ppt only when Q>Ksp
13But eure, i couldn't figure out a mistake.
Wht i imply is....
Salts will completely ionise first, (no reversible thing here), they're strong electrolytes.
So.... [M2+ ] = 0.01 & [S2- ]=0.01 (frm the salts alone)
Then these S2- ions again, will again cause common ion with H2S (which is already under common ion by HCl)....So, S2- frm H2S will all-the-more be decreased, which means S2- conc. can then be considered as coming frm the salt itself.
<< I hope the "0.01 M solns of salts.." they're are talking of are CuS & CdS only, not smthing like Cu(NO3)2 or others ...Is tht the point? >>