What should be the charge on CO3 in FeCO3 if the valency of iron is 2?
In FeCO3 :
It is given that valency of iron is 2 and we know that iron is a metal so it will donate its valence electrons to become the positively charged ion . So while forming FeCO3 molecule iron will give out 2 electrons to gain positive charge of +2 and CO3 has to accept 2 electrons to form the molecule.Therefore,CO3 on accepting 2 electrons will gain 2 negative charge and will become CO2−3.