Double Displacement Chemistry Example 2

Solution

1. 1
   Exchange partners: $\text{Ba}^{2+}$ pairs with $\text{SO}_4^{2-}$, $\text{Na}^+$ pairs with $\text{Cl}^-$.
2. 2
   Products: $\text{BaSO}_4$ and $\text{NaCl}$.
3. 3
   Balanced: $\text{BaCl}_2 + \text{Na}_2\text{SO}_4 \rightarrow \text{BaSO}_4\downarrow + 2\text{NaCl}$.
4. 4
   $\text{BaSO}_4$ is insoluble — it precipitates, driving the reaction forward.