For each reaction below, (a) identify the oxidation states of the atoms and (b) identify the oxidant, reductant, species oxidized, and species reduced. Also, think about this: How many electrons are transferred in each reaction?
O2 + 4 Fe2+ + 4 H3O+ ----> 6 H2O + 4 Fe3+
H2SO4 + ClO- --- -> S(s) + ClO4- + H2O