- What is the potential range (versus S.C.E.: Elsaturated KCI) = 0.241 V) over which the redox indicator phenosafranine (E -0.280 V versus S.H.E.) will change color? 0.039 to 0.521 v O 0.221 to 0.339 V O 0.0095 to 0.068 5V 0.079 to 0.157 v 0.020 to 0.098 V Consider the following redox reaction. MnO+5 Fe2+ +8H* --> Mn2+ 5 Fe3+ + 4 H 0 A0.588 2-8 sample of Fe(NH)2(SO4)2 + 6H20 (FM 392.14) is dissolved in 400 mL of 1.0 M H2SO4 and titrated with 0.0200 M KMnO.. Calculate the potential at the equivalence point versus a saturated calomel reference electrode (Esaturated KCI) = 0.241 V). Fe3+ + = Fe2+ C = 0.68V MnO4 +8H +5 --> Mn2 + 4H20 - 1.507 V e OE-0.853 v E - 1.369 V OE-0.577V OE - 1.128 V O E - 1.094 V