Barium nitrate is combined with sodium phosphate. When the balanced net ionic equation is constructed for this reaction, the stoichiometric coefficient for the barium ion will be
Among the compounds present in the reaction, Barium Nitrate, Sodium Phosphate and Sodium Nitrate are soluble ionic compounds. Hence, they will completely ionize into ions. Only BaSO4 is insoluble which becomes the precipitate. Ionic equation is:
Ba2+ + 2NO3- + 2Na+ + PO42- = 2Na+ +NO3- + BaPO4
Cancel like ions,
Ba2+ + PO42- = BaPO4.
Thus, the stoichiometric coefficient of Barium ion is 1.