Ionic Reactions in Aqueous Solutions

Key Concepts

• Ionic Reactions: Occur when ionic solids dissociate in solution and their ions rearrange to form new compounds.
• Aqueous Solutions: Compounds dissociated in solution.

Example Reaction

1. Reactants:

   • Aqueous calcium chloride (CaCl₂)
   • Silver nitrate (AgNO₃)

2. Products:

   • Aqueous calcium nitrate (Ca(NO₃)₂)
   • Solid silver chloride (AgCl)

Molecular Equation

• Displays the ionic substances involved but assumes compounds are intact.

Complete Ionic Equation

• Shows compounds split into their respective ions:
  • Calcium chloride (CaCl₂) → Ca²⁺ + 2Cl⁻
  • Silver nitrate (2AgNO₃) → 2Ag⁺ + 2NO₃⁻
  • Calcium nitrate (Ca(NO₃)₂) → Ca²⁺ + 2NO₃⁻
  • Silver chloride (AgCl) remains as AgCl (solid)

Net Ionic Equation

• Spectator Ions: Ions present on both sides of the equation that do not participate in the reaction (e.g., NO₃⁻ and Ca²⁺ can be ignored).
• Key Reaction:
  • Ag⁺ + Cl⁻ → AgCl (solid)

Summary

• Net Ionic Equations: Efficiently describe the chemistry between ionic solids in aqueous solutions by focusing on ions that undergo change.
• The example demonstrates that the true reaction is simply silver ions combining with chloride ions to form solid silver chloride.