If 1.00 g of Ca2+ dissolved in 420 mL of water reacts stoichiometrically according to the balanced equation in a reaction solution with a total volume of 1680 mL, what is the molarity (M) of Na+ produced?
CaCl2(aq) + Na2SO4(aq) → CaSO4(s) + 2 NaCl(aq)