Chapter 9.3, Problem 37PP

Interpretation Introduction

Interpretation:

The chemical, complete ionic and net ionic equation of reaction of aqueous solution of aluminium chloride and sodium hydroxide to form the precipitate of aluminium hydroxide needs to be written.

Concept introduction:

Chemical equation is the balanced chemical equation which shows the reactants and products using their chemical formulas. An ionic equation represents all the particles in a solution according to their existence and net ionic equations are the ionic equations that include only the particles participating in the reaction.

Answer to Problem 37PP

Chemical equation is as follows:

${\text{AlCl}}_{\text{3}}(aq)+3\text{NaOH}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)+3\text{NaCl}\text{(}aq\text{)}$

Complete ionic equation is as follows:

${\text{Al}}^{3+}\text{(}aq\text{)}\text{+}{\text{3Cl}}^{-}(aq)+3{\text{Na}}^{+}\text{(}aq\text{)}+3{\text{OH}}^{-}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)+3{\text{Na}}^{+}\text{(}aq\text{)}+3{\text{Cl}}^{-}\text{(}aq\text{)}$

Net ionic equation is as follows:

${\text{Al}}^{3+}\text{(}aq\text{)}+3{\text{OH}}^{-}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)$

Explanation of Solution

Chemical equation shows the reactants and products using chemical formulas. So, the chemical equation for the reaction of aqueous solution of aluminium chloride and sodium hydroxide to form the precipitate aluminium hydroxide is as follows:

${\text{AlCl}}_{\text{3}}(aq)+3\text{NaOH}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)+3\text{NaCl}\text{(}aq\text{)}$

The complete ionic equation shows ions of reactants and products. So, the complete ionic equation is as follows:

${\text{Al}}^{3+}\text{(}aq\text{)}\text{+}{\text{3Cl}}^{-}(aq)+3{\text{Na}}^{+}\text{(}aq\text{)}+3{\text{OH}}^{-}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)+3{\text{Na}}^{+}\text{(}aq\text{)}+3{\text{Cl}}^{-}\text{(}aq\text{)}$

In net ionic equation, the common ions in both sides of the reaction are cancelled. So, the net ionic equation is as follows:

$\begin{array}{l}{\text{Al}}^{3+}\text{(}aq\text{)}\text{+}\cancel{{\text{3Cl}}^{-}(aq)}+\cancel{3{\text{Na}}^{+}\text{(}aq\text{)}}+3{\text{OH}}^{-}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)+\cancel{3{\text{Na}}^{+}\text{(}aq\text{)}}+\cancel{3{\text{Cl}}^{-}\text{(}aq\text{)}}\\ {\text{Al}}^{3+}\text{(}aq\text{)}+3{\text{OH}}^{-}\text{(}aq\text{)}\to {\text{Al(OH)}}_{\text{3}}(s)\end{array}$

Conclusion

To show the details of reactions that involves ions in aqueous solutions, the ionic equations, such as, complete ionic equation and net ionic equations are used.