Chapter 2, Problem 50E

For each of the following pairs of ions, write the formula of the compound they will form:

1. ${\text{K}}^{+},{\text{O}}^{2-}$
2. ${\text{NH}}_4{}^{+},{\text{PO}}_4{}^{3-}$
3. ${\text{Al}}^{3+},{\text{O}}^{2-}$
4. ${\text{Na}}^{+},{\text{O}}_3{}^{2-}$
5. ${\text{Ba}}^{2+},{\text{PO}}_4{}^{3-}$