单项选择题
根据下列反应构成原电池,测得它的E〇=0.445V,已知E〇(I2/I)为0.535V,则电对S4O62-/S2O32-为()
A.-0.090V B.0.980V C.0.090V D.-0.980V
A.-0.68V B.+0.68V C.-0.34V D.+0.34V
A.Hg2+ B.MnO4- C.Cr2O2- D.Cl2