Question 9.5: Writing Equations for the Formation of an Insoluble Ionic Co......
Writing Equations for the Formation of an Insoluble Ionic Compound
When solutions of NaCl and AgNO_3 are mixed, a white solid forms. Write the ionic and net ionic equations for the reaction.
STEP 1 Write the ions of the reactants.
STEP 2 Write the combinations of ions, and determine if any are insoluble.
When we look at the ions of each solution, we see that the combination of Ag ^{+} and Cl^- forms an insoluble ionic compound.
STEP 3 Write the ionic equation including any solid. In the ionic equation, we show all the ions of the reactants. The products include the solid AgCl that forms along with the remaining ions Na ^{+}\text{ and }NO _3^{-}.
Ag ^{+}(a q)+ NO _3^{-}(a q)+ Na ^{+}(a q)+ Cl ^{-}(a q) \longrightarrow AgCl (s)+ Na ^{+}(a q)+ NO _3^{-}(a q)
STEP 4 Write the net ionic equation. We remove the Na ^{+}\text{ and }NO _3{ }^{-} ions, known as spectator ions, which are unchanged. This gives the net ionic equation, which only shows the ions that form a solid precipitate.
| Mixture (new combinations) | Product | Soluble |
| Ag ^{+}(a q)+ Cl ^{-}(a q) | AgCl | No |
| Na ^{+}(a q)+ NO _3^{-}(a q) | NaNO_{3} | Yes |
| Type of
Equation |
|
| Chemical | AgNO _3(a q) \quad+ NaCl (a q) \longrightarrow AgCl (s)+ NaNO _3(a q) |
| lonic | Ag ^{+}(a q)+ NO _3^{-}(a q)+ Na ^{+}(a q)+ Cl ^{-}(a q) \rightarrow AgCl (s)+ Na ^{+}(a q)+ NO _3^{-}(a q) |
| Net lonic | Ag ^{+}(a q) \quad+ Cl ^{-}(a q) \longrightarrow AgCl (s) |
