Chapter U4.90, Problem 7E

Interpretation Introduction

Interpretation:

Thecomplete and net ionic reaction for the precipitation reactions in pervious problem needs to be determined.

Concept Introduction:

When two soluble salts are combine to form insoluble salt is known as precipitation reaction.

When two reactant molecules exchange their ions to form two new compounds is known as double displacement reaction.

Answer to Problem 7E

  ${\text{CaCl}}_{\text{2}}\left(\text{aq}\right)\text{+}\text{2NaOH}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)\text{+}\text{2NaCl}\left(\text{aq}\right)$

The ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}{\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to {\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}\text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$

The complete ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$

Explanation of Solution

1. Double displacement reaction

The reaction is shown below:

  $\text{2NaCl }\left(\text{aq}\right)\text{+ Hg}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(\text{aq}\right)\to {\text{2NaNO}}_{\text{3}}\left(\text{aq}\right){\text{ + HgCl}}_{\text{2}}\left(\text{aq}\right)$

2. Precipitation reaction

When calcium chloride reacts with sodium hydroxide it will form precipitate of calcium hydroxide and sodium chloride.

The precipitation reaction is shown below:

  ${\text{CaCl}}_{\text{2}}\left(\text{aq}\right)\text{+}\text{2NaOH}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)\text{+}\text{2NaCl}\left(\text{aq}\right)$

The ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}{\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to {\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}\text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$

Na+ and Cl- is a spectator ion which are present on the reactant and product side. So, they are cancelling out to each other.

The complete ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$

3. Double displacement reaction

The reaction is shown below:

  ${\text{K}}_{\text{2}}{\text{CO}}_{\text{3}}\left(\text{aq}\right)\text{+}{\text{LiNO}}_{\text{3}}\left(\text{aq}\right)\to {\text{KNO}}_{\text{3}}\left(\text{aq}\right)\text{+}{\text{Li}}_{\text{2}}{\text{CO}}_{\text{3}}\left(\text{aq}\right)$

4. Double displacement reaction

The reaction is shown below:

  $\text{3Zn}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(\text{aq}\right){\text{ + 2Na}}_{\text{3}}{\text{PO}}_{\text{4}}\left(\text{aq}\right)\to {\text{ 6NaNO}}_{\text{3}}\left(\text{aq}\right){\text{+ Zn}}_{\text{3}}{\left({\text{PO}}_{\text{4}}\right)}_{\text{2}}\left(\text{aq}\right)$

5. Double displacement reaction

The reaction is shown below:

  ${\text{2NaNO}}_{\text{3}}\left(\text{aq}\right){\text{ + CaCl}}_{\text{2}}\left(\text{aq}\right)\to \text{ 2NaCl}\left(\text{aq}\right)\text{ + Ca}{\left({\text{NO}}_{\text{3}}\right)}_{\text{2}}\left(\text{aq}\right)$

Conclusion

  ${\text{CaCl}}_{\text{2}}\left(\text{aq}\right)\text{+}\text{2NaOH}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)\text{+}\text{2NaCl}\left(\text{aq}\right)$

The ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}{\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to {\text{2Na}}^{\text{+}}\left(\text{aq}\right)\text{+}{\text{2Cl}}^{\text{-}}\left(\text{aq}\right)\text{+}\text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$

The complete ionic reaction is shown below:

  ${\text{Ca}}^{\text{2+}}\left(\text{aq}\right)\text{+}{\text{2OH}}^{\text{-}}\left(\text{aq}\right)\to \text{Ca}{\left(\text{OH}\right)}_{\text{2}}\left(\text{s}\right)$