Question

If aqueous solutions of Na2SO4 and BaCl2 are mixed, does a precipitate form? If yes, identify the precipitate and the spectator ions.

Answer 1

Answer:- A precipitate of
`BaSO_4` is formed and the spectator ions are
`Na^+` and
`Cl^-` .

Explanations:- A double replacement reaction takes place. In double replacement reaction, the ion exchange takes place and we write the products. Then we use the solubility chart to check if a precipitate forms.

The balanced molecular equation is:

`Na_2SO_4(aq)+BaCl_2(aq)\rightarrow 2NaCl(aq)+BaSO_4(s)`

From solubility chart barium sulfate is insoluble so its precipitate is formed. sodium and chlorine ions are spectator ions as shown in the below ionic equation.

`2Na^+(aq)+SO_4^-^2(aq)+Ba^+^2(aq)+2Cl^-(aq)\rightarrow 2Na^+(aq)+2Cl^-(aq)+BaSO_4(s)`

The net ionic equation is:

`SO_4^-^2(aq)+Ba^+^2(aq)\rightarrow BaSO_4(s)`

So, the spectator ions are
`Na^+` and
`Cl^-` and a precipitate of
`BaSO_4` is formed.