InterviewSolution
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InterviewSolution
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`K_(a)` for the ionisation of `Fe^(3+)` to `Fe(OH)^(2+)` and `H^(o+)` is `6.5 xx 10^(-3)`, what is the maximum `pH` value which could be used so that at least `95%` of the total `Fe^(3+)` in a dilute solution exists as `Fe^(3+)`? |
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Answer» `{:(Fe^(3+)+,H_(2)OhArr,Fe(OH)^(2+)+,H^(+),,K_(h)=6.5xx10^(-3)),((1-h),,h,h,):}` `[H^(o+)] = Ch` and `K_(h) = (C.h^(2))/(1-h)` and `h = (5)/(100)` Thus, `6.5 xx 10^(-3) = (C xx5xx5xx100)/(100xx100xx95)` `:. C = 2.47 M :. [H^(o+)] = 2.47 xx (5)/(100)` `:. pH = 0.9083` |
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