You don't work out oxidation states by counting the numbers of electrons transferred. We're working on getting this fixed. The oxidation number of O in Li20 and KN03 is -2. What are the disadvantages of primary group? See the answer. In this reaction copper undergoes reduction where as iron gets oxidized. Preparing for entrance exams? Lower hydrates of zinc sulfate are rarely found in nature: (Zn,Fe)SO4•6H2O (bianchite), (Zn,Mg)SO4•4H2O (boyleite), and (Zn,Mn)SO4•H2O (gunningite). Similarly, Cu2+ is undergoing reduction or being reduced or acting as an oxidizing agent. Hi Hi Puffy Amiyumi Reboot, Chegg Tutors makes it easy to find a great tutor and connect instantly. This has to deal with the number of valence electrons and oxidation number of an element. Oxidation number of Zn changes from 0 to +2, and the oxidation number of Cu goes from 2+ to 0. Jeff Allen Family, received from your tutor.