Ionic Reaction

1. Review

  Question1£ºIn the following substances£¬which of them can react with each other?

             CuSO4   Ba(OH)2   HCl    Na2CO3

  Question2: Which type of these reactions above?

2. Introduction

  Question3: Have you ever considered the essence of the double-replacement reactions?

  Experimental investigation

        What happens when you put AgNO3 and NaCl in water?

Ag+(aq)+ NO3-(aq)+ Na+(aq)+ Cl-(aq) AgCl(s)+ NO3-(aq)+ Na+(aq)

3. Detailed interpretation

   Ionic Reaction: represented by cations and anions.

      For double-replacement rxns(or precipitate rxns), the reaction will occur if any product is:

     Spectator Ion & Net Ionic Equation :

         Spectator Ion: necessary but not directly participate in chemical reaction;

         Net Ionic Equation : focuses only on the ions REACTING.

4. Principle

(1) Precipitate£ºBaSO4¡¢CaCO3¡¢BaCO3

    Weak acid£ºH3PO4¡¢H2SO3¡¢HF¡¢H2CO3¡¢H2S¡¢CH3COOH¡¢HClO

   Weak base£ºNH3¡¢Al(OH)3¡¢Fe(OH)3¡¢Cu(OH)2

(2) Ratio of stoichiometric number must be minimum integer ratio.