Answer:
20. Mg(NO3)2
21. KClO3
22. CaSO4
23. (NH4)2SO4
24. HC2H3O
25. CO is carbon dioxide, which is neutral and would not combine with a hydrogen ion. Did you mean H and CO3(2-)? That would be H2CO3 (carbonic acid)
Step-by-step explanation:
You have to match the charges of the Cations and Anions.