Number of moles  of carbon atoms present in 1 mole of  Calcium carbonate are ( NA =Avagadro's number)

Atomicity of CaCO3 is 5 ;One molecule of CaCO3 contains…1 atom of ‘Ca’….1 atom of ‘C’…3 atoms of ‘O’…5 atoms ;One mole of CaCO3 contains…1 gram atom or 1 mole of ‘Ca’(NA)….1 gram atom or 1 mole,of ‘C’(NA)…3 gram atoms or 3 mole atoms of ‘O' (3NA)One mole of CaCO3 contains….5 gram atoms (5NA) ;One mole of CaCO3 contains…NA molecules ;One mole of CaCO3 contains….2 moles(2NA) of ions…One mole(NA) of Ca2+…One mole(NA) of CO32- CaCO3⇌Ca2++CO32- ;