Chapter 12, Problem 106A

(a)

Interpretation Introduction

Interpretation: The spectator ions in the equation $\text{Ba}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(aq\right)+{\text{Na}}_2{\text{SO}}_4\left(aq\right)\to {\text{BaSO}}_4\left(s\right)+{\text{NaNO}}_3\left(aq\right)$ is to be identified.

Concept Introduction: Dissolved ionic substances are represented as dissociated free ions in the ionic equation. The net ionic equation does not involve the spectator ions.

Answer to Problem 106A

  ${\text{Na}}^{+}$ and ${\text{NO}}_3^{-}$ are the spectator ions.

Explanation of Solution

The given chemical equation is as follows:

  $\text{Ba}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(aq\right)+{\text{Na}}_2{\text{SO}}_4\left(aq\right)\to {\text{BaSO}}_4\left(s\right)+{\text{NaNO}}_3\left(aq\right)$

The balanced chemical equation is as follows:

  $\text{Ba}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(aq\right)+{\text{Na}}_2{\text{SO}}_4\left(aq\right)\to {\text{BaSO}}_4\left(s\right)+2{\text{NaNO}}_3\left(aq\right)$

The ionic equation is as follows:

  ${\text{Ba}}^{2+}\left(aq\right){\text{+2NO}}_3^{-}\left(aq\right)+2{\text{Na}}^{+}\left(aq\right)+{\text{SO}}_4^{2-}\left(aq\right)\to {\text{BaSO}}_4\left(s\right)+2{\text{Na}}^{+}\left(aq\right)+{\text{2NO}}_3^{-}\left(aq\right)$

  ${\text{Na}}^{+}$ and ${\text{NO}}_3^{-}$ appear on both sides of an equation. Hence, they can cancel out.

The net ionic equation is as follows:

  ${\text{Ba}}^{2+}\left(aq\right)+{\text{SO}}_4^{2-}\left(aq\right)\to {\text{BaSO}}_4\left(s\right)$

Therefore, ${\text{Na}}^{+}$ and ${\text{NO}}_3^{-}$ are spectator ions.

(b)

Interpretation Introduction

Interpretation: The spectator ions in the equation ${\text{AlCl}}_3\left(aq\right)+{\text{AgNO}}_3\left(aq\right)\to \text{AgCl}\left(s\right)+\text{Al}{\left({\text{NO}}_3\right)}_3\left(aq\right)$ is to be identified.

Concept Introduction: Dissolved ionic substances are represented as dissociated free ions in the ionic equation. The net ionic equation does not involve the spectator ions.

Answer to Problem 106A

  ${\text{Al}}^{3+}$ and ${\text{NO}}_3^{-}$ are the spectator ions.

Explanation of Solution

The given chemical equation is as follows:

  ${\text{AlCl}}_3\left(aq\right)+{\text{AgNO}}_3\left(aq\right)\to \text{AgCl}\left(s\right)+\text{Al}{\left({\text{NO}}_3\right)}_3\left(aq\right)$

The balanced chemical equation is as follows:

  ${\text{AlCl}}_3\left(aq\right)+3{\text{AgNO}}_3\left(aq\right)\to 3\text{AgCl}\left(s\right)+\text{Al}{\left({\text{NO}}_3\right)}_3\left(aq\right)$

The ionic equation is as follows:

  ${\text{Al}}^{3+}\left(aq\right)+3{\text{Cl}}^{-}\left(aq\right)+3{\text{Ag}}^{+}\left(aq\right)+3{\text{NO}}_3^{-}\left(aq\right)\to 3\text{AgCl}\left(s\right)+{\text{Al}}^{3+}\left(aq\right)+3{\text{NO}}_3^{-}\left(aq\right)$

  ${\text{Al}}^{3+}$ and ${\text{NO}}_3^{-}$ are appear on both sides of an equation. Hence, they can cancel out.

The net ionic equation is as follows:

  $3{\text{Cl}}^{-}\left(aq\right)+3{\text{Ag}}^{+}\left(aq\right)+\to 3\text{AgCl}\left(s\right)$

Therefore, ${\text{Al}}^{3+}$ and ${\text{NO}}_3^{-}$ are the spectator ions.

(c)

Interpretation Introduction

Interpretation: The spectator ions in the equation ${\text{H}}_2{\text{SO}}_4\left(aq\right)+\text{Mg}{\left(\text{OH}\right)}_2\left(aq\right)\to {\text{MgSO}}_4\left(aq\right)+{\text{H}}_{\text{2}}\text{O}\left(l\right)$ is to be identified.

Concept Introduction: Dissolved ionic substances are represented as dissociated free ions in the ionic equation. The net ionic equation does not involve the spectator ions.

Answer to Problem 106A

  ${\text{Mg}}^{2+}$ and ${\text{SO}}_4^{2-}$ are the spectator ions.

Explanation of Solution

The given chemical equation is as follows:

  ${\text{H}}_2{\text{SO}}_4\left(aq\right)+\text{Mg}{\left(\text{OH}\right)}_2\left(aq\right)\to {\text{MgSO}}_4\left(aq\right)+{\text{H}}_{\text{2}}\text{O}\left(l\right)$

The balanced chemical equation is as follows:

  ${\text{H}}_2{\text{SO}}_4\left(aq\right)+\text{Mg}{\left(\text{OH}\right)}_2\left(aq\right)\to {\text{MgSO}}_4\left(aq\right)+2{\text{H}}_{\text{2}}\text{O}\left(l\right)$

The ionic equation is as follows:

  ${\text{2H}}^{+}\left(aq\right)+{\text{SO}}_4^{2-}\left(aq\right)+{\text{Mg}}^{2+}\left(aq\right)+2{\text{OH}}^{-}\left(aq\right)\to {\text{Mg}}^{2+}\left(aq\right)+{\text{SO}}_4^{2-}\left(aq\right)+2{\text{H}}_{\text{2}}\text{O}\left(l\right)$

  ${\text{Mg}}^{2+}$ and ${\text{SO}}_4^{2-}$ are appear on both sides of an equation. Hence, they can cancel out.

The net ionic equation is as follows:

  ${\text{2H}}^{+}\left(aq\right)+2{\text{OH}}^{-}\left(aq\right)\to 2{\text{H}}_{\text{2}}\text{O}\left(l\right)$

Therefore, ${\text{Mg}}^{2+}$ and ${\text{SO}}_4^{2-}$ are the spectator ions.