InterviewSolution
Saved Bookmarks
| 1. |
Redox reactions play a pivotal role in chemistry and biology. The values of standard redox potential `(E^(@))` of two half-cell reactions decide which way the reaction is expected to proceed. A simple example is Daniel Cell in which zinc goes into solution and copper gets deposited. Given below are a set of half-cell reactions (acidic medium) aong with their `E^(@)` (V with respect to normal hydrogen electrode) values. `{:(I_(2)+2e^(-) rarr 2I^(-),E^(@)=0.54),(Cl_(2) +2e^(-) rarr 2Cl^(-),E^(@)=1.36),(Mn^(3+)+e^(-)rarr Mn^(2+),E^(@)=1.50),(Fe^(3+)+e^(-) rarr Fe^(2+),E^(@)=0.77),(O_(2)+4H^(+)+4e^(-) rarr 2H_(2)O,E^(@)=1.23):}` Using these data, obtain the correct explanation for the following questions. Among the following, identify the correct statementA. Chloride ion is oxidised by `O_(2)`B. `Fe^(2+)` is oxidised by iodideC. Iodide ion is oxidised by chlorineD. `Mn^(2+)` is oxidised by chlorine |
|
Answer» Correct Answer - C Calculate the EMF of all the cells. Only the EMF of the cell involving the oxidation of `I^(-)` ion by `Cl_(2)` is +ve. `{:(2I^(-) rarr I_(2)+2e^(-)", "E^(@)=-0.54 V),(Cl_(2)+2e^(-) rarr 2Cl^(-)", "E^(@)=+1.36 V),(bar(Cl_(2)+2I^(-) rarr 2Cl^(-)+I_(2), E_("cell")^(@)+0.82 V)):}` Thus, option (c) is correct. |
|