Question

may i know if CO32- can oxidise further?

Answer 1

Hey,I think no it cannot be further oxidised because looking at the oxidation states of each element in the carbonate anion. Check them Carbon has +4 and oxygen is always -2 but because 3 oxygen atoms are present. oxygen has a charge of -6 and the overall charge of the compound is -2 therefore carbon must be +4
Carbon has electronic configuration of 2,4 +4 indicates that 4 electrons are lost and if were left with only 2 electrons in the energy level then the atom is stable and is not in need to either loose or gain more electrons

Answer 2

sorry Oxidation Number ** not state