# When solutions of barium chloride (aq) and sodium sulfate (aq) are mixed, what is/are the spectator ion(s)?

Dec 2, 2016

$\text{Sodium and chloride ions.........}$

#### Explanation:

We write the equation for the formation of $B a S {O}_{4} \left(s\right)$ as:

$B a C {l}_{2} \left(a q\right) + N {a}_{2} S {O}_{4} \left(a q\right) \rightarrow B a S {O}_{4} \left(s\right) \downarrow + 2 N a C l \left(a q\right)$

Alternatively, we could write the net ionic equation:

$B {a}^{2 +} + S {O}_{4}^{2 -} \rightarrow B a S {O}_{4} \left(s\right) \downarrow$

In other words, the $N {a}^{+}$, and $C {l}^{-}$ ions are along for the ride. The are passengers, spectators, and play no part in the macroscopic reaction.