Chapter 6, Problem 7RQ

Interpretation Introduction

Interpretation: The complete ionic equation, net ionic equation and the formula equation of the given reaction has to be differentiated.

Concept Introduction: Chemical compound that contains ions are held together by electrostatic forces called as ionic bonding. These compounds are completely neutral in nature but they consist of positively charged ions called as cations and negatively charged ions called as anions. Those ionic compounds without any ions are called as salts and they formed in an acid-base reaction. Ionic compound those contain hydrogen ions are called as acids and those containing hydroxide or oxide ion are called as bases.

Answer to Problem 7RQ

Answer

The formula equation, complete ionic equation and net ionic equation of ${\text{Na}}^{\text{+}}{\text{,Br}}^{\text{-}}{\text{,Pb}}^{\text{2+}}{\text{,NO}}_{\text{3}}{}^{\text{-}}$ can be given as,

$\begin{array}{l}{\text{2NaBr}}_{\left(\text{aq}\right)}{\text{+Pb(NO}}_{\text{3}}{\text{)}}_{\text{2(aq)}}\to {\text{PbBr}}_{\text{2(s)}}{\text{+2NaNO}}_{\text{3(aq)}}\mathrm{......}\text{(1)}\\ {\text{2Na}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+2Br}}^{\text{-}}{}_{\left(\text{aq}\right)}{\text{+Pb}}^{\text{2+}}{}_{\left(\text{aq}\right)}{\text{+2NO}}_{\text{3}}{{}^{\text{-}}}_{\left(\text{aq}\right)}\to {\text{PbBr}}_{\text{2}\left(\text{s}\right)}{\text{+2Na}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+2NO}}_{\text{3}}{{}^{\text{-}}}_{\left(\text{aq}\right)}\mathrm{......}\text{(2)}\\ {\text{Pb}}^{\text{2+}}{}_{\left(\text{aq}\right)}{\text{+2Br}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{PbBr}}_{\text{2}\left(\text{s}\right)}\mathrm{......}\text{(3)}\end{array}$

The formula equation, complete ionic equation and net ionic equation of ${\text{Al}}^{\text{3+}}{\text{,Cl}}^{\text{-}}{\text{,K}}^{\text{+}}{\text{,OH}}^{\text{-}}$ can be given as,

$\begin{array}{l}{\text{AlCl}}_{\text{3}}{}_{\left(\text{aq}\right)}{\text{+3KOH}}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}{\text{+3KCl}}_{\left(\text{aq}\right)}\mathrm{......}\text{(4)}\\ {\text{Al}}^{\text{3+}}{}_{\left(\text{aq}\right)}{\text{+3Cl}}^{\text{-}}{}_{\left(\text{aq}\right)}{\text{+3K}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+3OH}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}{\text{+3K}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+3Cl}}^{\text{-}}{}_{\left(\text{aq}\right)}\mathrm{......}\text{(5)}\\ {\text{Al}}^{\text{3+}}{}_{\left(\text{aq}\right)}{\text{+3OH}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}\mathrm{......}(6)\end{array}$

Equation 1 and 4 are formula equation.

Equation 2 and 5 are complete ionic equation.

Equation 3 and 6 are net ionic equation.

Explanation of Solution

Explanation

Formula equation contains all the ions together.

The soluble ionic compounds are shown as separate ions and the precipitate is shown together, such an equation is called as complete ionic equation.

Net ionic equation contains those ions that help in the formation of precipitate.

Soluble ionic compounds are indicated with (aq) that make them exists as separate ions in the solution, and those ions that helps in the formation of precipitate come together. This is called as formula equation where all the ions are seen in combined way.

In a complete ionic equation, the ionic compounds that are soluble are generally seen as separate ions and the precipitate is seen together.

In net ionic equation, the role of ions has no effect but instead they are used in balancing of charge. Those ions that help in balancing the charges are called as spectator ions and remain inside the solution. Only those ions that come together to form the precipitate are shown are seen in ionic equation.

The formula equation, complete ionic equation and net ionic equation of ${\text{Na}}^{\text{+}}{\text{,Br}}^{\text{-}}{\text{,Pb}}^{\text{2+}}{\text{,NO}}_{\text{3}}{}^{\text{-}}$ can be given as,

$\begin{array}{l}{\text{2NaBr}}_{\left(\text{aq}\right)}{\text{+Pb(NO}}_{\text{3}}{\text{)}}_{\text{2(aq)}}\to {\text{PbBr}}_{\text{2(s)}}{\text{+2NaNO}}_{\text{3(aq)}}\mathrm{......}\text{(1)}\\ {\text{2Na}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+2Br}}^{\text{-}}{}_{\left(\text{aq}\right)}{\text{+Pb}}^{\text{2+}}{}_{\left(\text{aq}\right)}{\text{+2NO}}_{\text{3}}{{}^{\text{-}}}_{\left(\text{aq}\right)}\to {\text{PbBr}}_{\text{2}\left(\text{s}\right)}{\text{+2Na}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+2NO}}_{\text{3}}{{}^{\text{-}}}_{\left(\text{aq}\right)}\mathrm{......}\text{(2)}\\ {\text{Pb}}^{\text{2+}}{}_{\left(\text{aq}\right)}{\text{+2Br}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{PbBr}}_{\text{2}\left(\text{s}\right)}\mathrm{......}\text{(3)}\end{array}$

The formula equation, complete ionic equation and net ionic equation of ${\text{Al}}^{\text{3+}}{\text{,Cl}}^{\text{-}}{\text{,K}}^{\text{+}}{\text{,OH}}^{\text{-}}$ can be given as,

$\begin{array}{l}{\text{AlCl}}_{\text{3}}{}_{\left(\text{aq}\right)}{\text{+3KOH}}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}{\text{+3KCl}}_{\left(\text{aq}\right)}\mathrm{......}\text{(4)}\\ {\text{Al}}^{\text{3+}}{}_{\left(\text{aq}\right)}{\text{+3Cl}}^{\text{-}}{}_{\left(\text{aq}\right)}{\text{+3K}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+3OH}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}{\text{+3K}}^{\text{+}}{}_{\left(\text{aq}\right)}{\text{+3Cl}}^{\text{-}}{}_{\left(\text{aq}\right)}\mathrm{......}\text{(5)}\\ {\text{Al}}^{\text{3+}}{}_{\left(\text{aq}\right)}{\text{+3OH}}^{\text{-}}{}_{\left(\text{aq}\right)}\to {\text{Al(OH)}}_{\text{3(s)}}\mathrm{......}(6)\end{array}$

Equation 1 and 4 are formula equation.

Equation 2 and 5 are complete ionic equation.

Equation 3 and 6 are net ionic equation.

Conclusion

Conclusion

The formula equation shows the ions total that takes place in the reaction. The complete ionic equation shows ions separately and the ions that form the precipitate are shown together. Net ionic equation shows the ions of the precipitate. The reactions were differentiated as formula equation, complete ionic equation and net ionic equation.