Chem 11106 study sheet for exam 3

Chp. 19  Solubility-Based Equilibria

1.             Know what a titration is including the definitions of equivalence point, titrant, analyte.

2.             Know how to work stoichiometry-based titration problems. 

3.             Be able to deal with the following flock of issues for both SASB and WASB titrations:

a.                    pH of initial sol’n?

b.                   What is the titration rxn?

c.                    pH after some titrant has been added?

d.                   pH at midway point?

e.                    how much titrant required to reach equivalence point?

f.                     PH at equivalence point?

g.                   What would be an appropriate indicator?

h.                   Difference between endpoint and equivalence point.

 

4.             Know what a Ksp is and how the equilibrium expression is formulated and used

5.             Be able to determine Ksp from molar solubility data

6.            Know solubility rules from Chp. 4 (p 143)

7.            Know how to find spectator ions and write net ionic equations (with phase symbols)

8.             Be able to determine molar solubility data from Ksp

9.             Be able to use Qsp to determine whether ppt will occur

10.            Strategy for dissolving a ppt.  (eliminate one of the ions* from the solubility equilibrium thus leaving the other freely solvated).

      *by either an acid-base rxn or can do it by complex ion formation.

11.             LeChatelier's interpretation of the above.

Chp. 23,  Complex Ion Formation

1.                    Know what the Lewis Acid/Base theory is (definitions, mechanisms, and its relation to Bronsted Acid/Base theory and complex ion formation)Geometries associated with the metal cations in complexes (you'll be provided with tetrahedral vs. sq. planar info as required).

2.                    Ligands - unidentate, bidentate…..; neutral vs. anionic, know structures of ox and en.

3.                    Know how to determine ox # of metal in complex ion.

4.                    Know the 3 different types of isomerism found in metal complexes that we discussed.

5.                    understand the difference between ligands and counterions.

6.                    Given a formula, be able to draw a geometrically reasonable picture of a complex ion.

Chp. 20,  Thermodynamics

1.                    Definition of Enthalpy and its attendant sign conventions.

2.                    DH by summation of DHof''s

3.                    Entropy -what it's about and sign conventions.

4.                    Qualitative trends associated with entropy.

5.                    Second Law of Thermodynamics

6.                    DSo by summation of So values.

7.                    Entropy trends

8.                    DGo  =  DHo - TDSo

9.                    Sign conventions for free energy.

10.                 DGo by summation and via eqn. in 9.

11.                 Determination of how changes in T will affect rxn spontaneity and calculation of threshold temps (where appropriate).

12.                 Relating free energy to equilibrium (be able to go both ways).

13.                 Determination of DG under nonstandard conditions.

15.      Third Law of Thermodynamics

Test format will be problems, draw pictures, chemical reactions, short answer.  It should be fun.  You bring the math equations in your head, I'll supply constants, conversion factors, and raw data (DH, DS, Ksp......).  Let me know what's going on as questions arise.  Approximate point values associated with each Chapter:

Chp 19                    40 points

Chp 23                    25 points

Chp 20                    35 points

 

Bring that non-programmable calculator of your's and an empty bladder.  Test starts at 11:25.