(i) ZnO, PbO and Sb2O3 show characteristics of both acids and bases as well. Therefore, they all amphoteric oxides. (ii) CO and NO are oxygen poor compounds of non-metals. Therefore, they all are neutral oxides. (iii) CrO‌3 , Mn‌2O‌7 , V‌2O‌5 form acidic oxides. Thus, all statements are incorrect