1. Plan for Tues/Wed, 13/14 Oct 08 Turn in Exp 3 Pre-lab
Today: Exp 3, Metathesis Reactions
Purpose:
To observe several metathesis reactions and develop a flow chart using solubility rules to identify an unknown solution.
To write net ionic equations for the reactions observed.
To observe the physical state of several compounds.
Turn in Exp 2 post-lab before you leave today

2. Tips for success Make sure your observations are very detailed!!
If no ppt forms in one of your tests on your unknown, make sure to perform the pH test…you may have NH4Cl.
You WILL NOT be given more of your unknown solution if you run out before you identify the cation and anion.
Avoid touching the AgNO3 solution. It will turn your skin black!!
HCl(aq) and NaOH(aq) are toxic and corrosive!! BE CAREFUL!!
NEVER put a spatula, etc into a reagent bottle. NEVER return unused reagent to the reagent bottle. Any unused reagent must be placed in the waste container.
DO NOT overfill the liquid waste containers. Let me know if they are getting too full and I will replace them.

3. Part B:
a) Draw flowchart that includes all possible tests.
b) Draw flowchart for just the tests you performed.

4. 2AgNO3(aq) + BaCl2(aq)  2AgCl(s) + Ba(NO3)2(aq)
BaCl2.2H2O(s)
AgNO3(aq)
BaCl2(aq) + AgNO3(aq)
Cl-
NO3-
Cl-
NO3-
Ba2+
Ag+
Ag+
Cl-
Cl-
Ba2+
Ag+
Cl-
Ag+
NO3-
NO3-
Ba2+
Cl-
Cl-
Ba2+
Cl-
2AgNO3(aq) + BaCl2(aq)  2AgCl(s) + Ba(NO3)2(aq)
Barium and nitrate ions are left in aqueous solution.
Solid silver chloride precipitates out of solution.

5. Total and Net Ionic Equations
Conventional equation: a bookkeeping of all species present, and arranged for charge neutrality.
BaCl2(aq) + 2AgNO3(aq)
Ba(NO3)2(aq) AgCl(s)
Total Ionic equation: all aqueous species are split up into their component ions.
Ba2+(aq) + 2Cl-(aq) + 2Ag+(aq) + 2NO3-(aq)
2AgCl(s) + Ba2+(aq) + 2NO3-(aq)
Na+ and NO3- are spectator ions in this reaction…they are not involved in the chemical change.
Net Ionic equation: indicates exactly the chemical change that occurs, and nothing more.
2Ag+(aq) + 2Cl-(aq)
AgCl(s)