1. Chem. 1B – 11/22 Lecture

2. Announcements I Lab Exam 3 No Lab this Wednesday (or Thursday)
Next Week on Thursday
On electrochemistry and Chapter 24
Help Session Tues. afternoon (joint with PALs?? – I can do 4:00 to 5:00)

3. Announcements II Mastering Today’s Lecture Ch. 24 assignment due 11/26
Transition Elements (Ch. 24)
Properties of Coordination Complexes – light absorption and magnetic properties - Completing
Exam 3 Material + Some Practice Problems
Organic Chemistry (Ch. 20)

4. Chapter 24 Transition Metals
Questions – cont. from last time
Ti3+ is purple while Ti4+ is uncolored. Explain.
For which of the following metals in octahedral complexes does the ligand NOT play a role in the number of unpaired electrons?
a) Mn2+ b) Fe3+ c) Co2+ d) Ni2+
6. [Fe(en)3]3+ undergoes a ligand replacement reaction and forms [FeX6]3-. The new complex absorbs at shorter wavelengths. What do we know about the strength of X as a ligand?

5. Exam 3 Review Equations I will give: Equations you should know:
DGrxn = DGrxn° + RTlnQ (more Thermo)
DG° = -nFE° and E° = E°cell - (0.0592/n)logQ
Equations you should know:
q = It (constant I); q = nF
Ecell° = Ered° - Eox°
E (= D) = hc/l

6. Exam 3 Review – Chapter 18 Redox Reactions
Be able to determine oxidation states
Determine which element is being reduced and which is being oxidized
Know all steps in reaction balancing and be able to apply (see example questions)
Know three ways in which redox reactions can occur (beakers, voltaic cells, electrolytic cells)

7. Exam 3 Review – Chapter 18 Voltaic Cells
Know components of voltaic cell (anode, cathode, cell bridge, rest of circuit)
Know charge of and reaction type at each electrode
Know flow (direction) of electrons and ions
Know purpose of voltaic cell
Know cell notation

8. Exam 3 Review – Chapter 18 Standard Electrode (Reduction) Potentials
Know basis (how it could be measured)
Know standard conditions
Be able to use table to:
Determine E°cell (from combining two standard electrodes) + reaction direction
Know what makes a good reducing/oxidizing agent
What metals can be oxidized in acid

9. Exam 3 Review – Chapter 18 Relating Thermodynamics to Cell Potential
Be able to convert between DG°, K, and E°
Know standard conditions
Use of the Nernst Equation:
For calculation of Ecell (non-standard conditions)
For determination of concentration
For determination of E°cell (from Emeasured and Q)

10. Exam 3 Review – Chapter 18 Batteries (Application of Voltaic Cells)
Be able to relate charge or lifetime to moles of reactants (q = nF)
Know requirements for rechargeable batteries
Know fuel cell basics
Electrolysis
Know main differences with voltaic cells
Be able to predict reduction/oxidation reactions

11. Exam 3 Review – Chapter 18 Corrosion
Understand tendency of metals to oxidize
Understand requirement of sacraficial metals

12. Exam 3 Review – Chapter 24 Transition Metal Names
Know names of row 4 elements + d8 to d10 (row 5 and 6)
Transition Metal Properties
Know electron configurations of transition metals plus ions (including rule exceptions in first row)
Know size (mostly decreases across row) and oxidation state trends

13. Exam 3 Review – Chapter 24 Coordination Complexes
Know requirement for ligands
Know types of ligands (mono-, bi-, polydentate)
Know major geometries (linear, square planar, tetrahedral, octahedral) plus associated ligand numbers and structures
Know how to relate name to formulas (we are not worrying about bis-, linkage ligands in names, and a table of latin roots will be provided)

14. Exam 3 Review – Chapter 24 Coordination Complexes - Isomers
Know what structural isomers are
Know requirement for linkage isomers
Be able to tell if cis- trans- or fac- mer- isomers exist
Know what optical isomers are
Be able to predict the correct number of isomers

15. Exam 3 Review – Chapter 24 Bonding Theory
Know where metal ligand bonds come from
Know which d orbitals overlap more with ligand bonds in octahedral complexes and which overlap less
Know how overlap leads to a split in the d orbital energies
Know difference between low spin and high spin filling of d orbitals

16. Exam 3 Review – Chapter 24 Bonding Theory – cont.
Know how ligand (e.g. strong vs. weak) affects filling and D of coordination complexes
Know how metal charge affects D of coordination complexes
Be able to predict the d orbital electron configuration of coordination complexes (if known whether ligand is strong or weak)
Know what causes coordination complexes to absorb light in visible, plus be able to calculate l from D or visa versa

17. Exam 3 Review – Chapter 24 Bonding Theory – cont.
Be able to determine number of unpaired electrons and how that affects magnetic properties of complexes
Understand why differences in energy levels occur for other geometries (tetrahedral, square planar)

18. Exam 3 Review – Questions I
Reaction
E°(V)
Ag+(aq) + e- ↔ Ag(s)
+0.80
Cu2+(aq) + 2e- ↔ Cu(s)
+0.34
2H+(aq) + 2e- ↔ H2(g)
0.00
Ni2+(aq) + 2e- ↔ Ni(s)
-0.23
Cd2+(aq) + 2e- ↔ Cd(s)
-0.40
Fe2+(aq) + 2e- ↔ Fe(s)
-0.45
1. Which of the metals (in oxidation state of zero) in the list above are oxidized by H+?
Ni and Cd b) Ni only c) Cd only d) Cu and Ag e) Ni, Cd, and Fe
2. In the following cell, the measured voltage is 0.99 V. Determine x (the concentration of AgNO3(aq) in half of the cell.
cell: Ni(s)|NiCl2(aq, 1.0 M)||AgNO3(aq, x M)|Ag(s)
0.21 M b) M c) M d) 2.2 M e) 4.8 M

19. Exam 3 Review – Questions II
Reaction
E°(V)
Ag+(aq) + e- ↔ Ag(s)
+0.80
Cu2+(aq) + 2e- ↔ Cu(s)
+0.34
2H+(aq) + 2e- ↔ H2(g)
0.00
Ni2+(aq) + 2e- ↔ Ni(s)
-0.23
Fe2+(aq) + 2e- ↔ Fe(s)
-0.45
3. Which of the following reactants can oxidize copper metal (Cu(s)) under standard conditions?
a) Ag+(aq) b) H+(aq) c) Ni2+(aq) d) Fe2+(aq) e) any of these
4. A voltaic cell is made under standard conditions by Fe(s) and FeCl2(aq) in one half cell and AgNO3(aq) and Ag(s) in another half cell. The voltage from the silver (+) to the iron electrode (-) will be:
a) V b) V c) V d) V e) V

20. Exam 3 Review – Questions III
The following reaction is an UNBALANCED reaction showing reactants and products of a redox reaction:
HClO(aq) + Cr(s) ↔ Cl2(g) + Cr3+(aq)
When balanced (can assume acidic conditions), the coefficients in front of HClO and Cr (with no fractional coefficients anywhere in the equation) are:
1 and 1 b) 2 and 1 c) 3 and 1 d) 3 and 2
e) 6 and 2, respectively.
6. In coordination complexes, electrons in bonds between ligands and metals almost always come from:
a) metal s shells b) metal d shells c) ligand lone pair electrons
d) ligand inner shell electrons e) ligand sigma bonds

21. Exam 3 Review – Questions IV
7. Given the complex [Co(NO2)6]4- , give a) oxidation state on Co b) # d shell electrons, c) # unpaired electrons if you know NO2- is a strong ligand 8. Can the above compound form any isomers?

22. Chapter 20 Organic Chemistry
Introduction
Organic Chemistry is a major area of study (we offer 7 organic chemistry classes at the undergraduate level)
In ~1 week, we only have time to introduce basic principles of organic chemistry

23. Chapter 20 Organic Chemistry
Overview
Nature of Carbon – Carbon Bonds
Hydrocarbons (structure, naming and isomers)
Reactions
Aromatic Hydrocarbons
Functional Groups

24. Chapter 20 Organic Chemistry
Nature of Carbon – Carbon Bonds
Carbon is one of the few elements that form fairly stable bonds with itself
Most alkanes (hydrocarbons with only single bonds), while combustible in air (more stable as CO2 + H2O), have negative DGfº
Carbon “likes to” form 4 bonds ([He]2s22p2, but mostly forms sp to sp3 hybrid bonds)

25. Chapter 20 Organic Chemistry
Nature of Carbon – Carbon Bonds
Simplest hydrocarbon is CH4, methane, in which sp3 hybridization occurs (tetrahedral geometry)
As carbon – carbon bonds are common, in alkanes, they also occur with sp3 hybridization (tetrahedral for each C atom)