"Hard" water is hard because it contains Ca2+(aq) and Mg2+(aq) ions. It can be softened by adding borax powder, which is sodium tetraborate, Na2B4O7. Adding borax removes the Ca2+(aq) and Mg2+(aq) from solution. Write a net ionic equation for each of these two reactions. What ion replaces the Ca2+(aq) and Mg2+(aq) ions in the water?