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A solution containing Cu^(2+) and C_(2)O_(4)^(2-) ions is titrated with 20 " mL of " (M)/(4) KMnO_(4) solution in acidic medium. The resulting solution is treated with excess of KI after neutralisation. The evolved I_(2) is then absorbed is 25 " mL of " (M)/(10) hypo solution. Which of the following statements are correct?

Answer» <html><body><p>The difference of the number of m " mol of "`Cu^(2+)` and `C_(2)O_(<a href="https://interviewquestions.tuteehub.com/tag/4-311707" style="font-weight:bold;" target="_blank" title="Click to know more about 4">4</a>)^(2-)` ions in the <a href="https://interviewquestions.tuteehub.com/tag/solution-25781" style="font-weight:bold;" target="_blank" title="Click to know more about SOLUTION">SOLUTION</a> is 10 m mol<br/>The difference of the number of m " mol of "`Cu^(2+)` and `C_(2)O_(4)^(2-)` ions in the solution is 22.5 m mol.<br/>The equivalent weight of `Cu^(2+)` ions in the titration with KI is equal to the atomic weight of `Cu^(2+)`<br/>The equivalent weight of KI in the titratio is `(M)/(2)` `(M=` molesular weight of KI)</p>Solution :(i). `Cu^(2+)` does not react with `MnO_(4)^(ɵ)` <br/> Only `C_(2)O_(4)^(2-)` reacts with `MnO_(4)^(2-)` <br/> `MnO_(4)^(ɵ)=C_(2)O_(4)^(2-)` <br/> `(n=5)(n=2)` <br/> `mEq-=mEq` <br/> `20xx(M)/(4)xx5-=mEq` <br/> `thereforem" Eq of "C_(2)O_(4)^(2-)=25` <br/> `mmoles of `C_(2)O_(4)^(2-)=(25)/(2)=12.5` <br/> (<a href="https://interviewquestions.tuteehub.com/tag/ii-1036832" style="font-weight:bold;" target="_blank" title="Click to know more about II">II</a>). `Cu^(2+)=KI-=I_(2)=S_(2)O_(3)^(2-)` (hypo) <br/> `mEq-=mEq-=mEq-=mEq` <br/> `(2Cu^(2+)+2I^(ɵ)toCu_(2)I_(2))(2S_(2)O_(3)^(2-)to_S_(4)O_(6)^(2-)+2e^(-))` <br/> `(e+Cu^(2+)toCu^(<a href="https://interviewquestions.tuteehub.com/tag/1-256655" style="font-weight:bold;" target="_blank" title="Click to know more about 1">1</a>+))` <br/> `m" Eq of "S_(2)O_(3)^(2-)-=25xx(M)/(10)xx1` <br/> `=2.5m" Eq of "Cu^(2+)` <br/> `m" Eq of "Cu^(2+)=2.5` <br/> `mmoles of Cu^(2+)=(2.5)/(1)=2.5` <br/> Difference in mmoles of `C_(2)O_(4)^(2-)` and `Cu^(2+)=12.5-2.5=10` <br/> <a href="https://interviewquestions.tuteehub.com/tag/ew-447045" style="font-weight:bold;" target="_blank" title="Click to know more about EW">EW</a> of `Cu^(2+)=("atomic weight" of Cu^(2+))/(1("n-factor"=1))` <br/> Ew of `KI=(M)/("nfactor")=(M)/(1)=M{:(2I^(ɵ)toI_(2)+2e^(-)),(n=(2)/(2)=1):}`</body></html>


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