1. What is the importance of expressing a net ionic equation?

2. What is a NET IONIC EQN? The dictionary definition is: Chemical equation for a reaction which lists only those species participating in the reaction. MY definition is: An equation that shows only the reactants involved in the formation of a precipitate.

3. Key Terminology Net Ionic Equations : include ions that dissociate an aqueous solution, only those involved in the formation of a precipitate Precipitate = solid product that does not break apart Spectator Ion = ion that does not take part in the reaction

4. Watch This! http://www.crescent.edu.sg/crezlab/webpage s/PptReaction_AgCl.htm http://www.crescent.edu.sg/crezlab/webpage s/PptReaction_AgCl.htm Ppt  Ppt

5. Let’s Look at an Example! AgNO 3 (aq) + KCl (aq)  AgCl (s) + KNO 3 (aq) 1.Assign Charges to all species. +1 +1 +1 +1

6. +1 -1 +1 -1 AgNO 3 (aq) + KCl (aq)  AgCl (s) + KNO 3 (aq) Ag +1 NO 3 -1 + K +1 Cl -1  AgCl (s) + K +1 NO 3 -1 1.Assign Charges to all species. 2.Dissociate all (aq) species – SLOSHERS! 3.SOLIDS STAY (s) – do not dissociate.

7. AgNO 3 (aq) + KCl (aq)  AgCl (s) + KNO 3 (aq) Ag +1 + NO 3 -1 + K +1 + Cl -1  AgCl (s) + K +1 + NO 3 - 1 1.Assign Charges to all species. 2.Dissociate all (aq) species – SLOSHERS! 3.SOLIDS STAY (s) – do not dissociate. 4.Cross out spectators. Cross out spectators because they do not take place in the reaction. They are still floating around in the solution.

8. AgNO 3 (aq) + KCl (aq)  AgCl (s) + KNO 3 (aq) Ag +1 + NO 3 -1 + K +1 + Cl -1  AgCl (s) + K +1 + NO 3 -1 Ag +1 + Cl -1  AgCl (s) 1.Assign Charges to all species. 2.Dissociate all (aq) species – SLOSHERS! 3.SOLIDS STAY (s) – do not dissociate. 4.Cross out spectators. 5.Rewrite remaining. 6.Balance.

9. Try one! Pb(NO 3 ) 2 (aq) + AlCl 3 (aq)  Cu(SO 4 ) (aq) + Cal 2 (aq) 