What is the net ionic equation of #2H^+ + SO_4^(2-) + Ca^(2+) + 2I^- -> CaSO_4 + 2H^+ + 2I^-#?
Simply cancel out the ions that are COMMON as reactants and products......
And the questions you've gots to be asking yourself are:
Well are they? If they are not, then you have not made a reasonable representation of chemical reality.