Question 17 of 170

Standard potential data are usefull for understanding the suitability of an oxident in a redox titration. Some half cell reactions and their standard potentials are given ahead;

MnO4-(aq) + 8H+(aq) + 5e-                 Mn2+(aq) + 4H2O(l); E°=1.51VCr2O72-(aq) +14H+(aq) + 6e-      +2Cr3+ (aq) + 7H2O(l);E°=1.38VFe3+(aq) + e-           Fe2+(aq);                                                  E°=0.77VCl2(g) +2e-           2Cl-(aq);                                                       E°=1.40V

Identify the only incorrect statement regarding the quantitative estimation of aqueous Fe(NO3)2:

(a) MnO4- can be used in aqueous HCl

(b) Cr2O72-can be used in aqueous HCl

(c) MnO4-can be used in aqueous H2SO4

(d) Cr2O72-can be used in aqueous H2SO4