Students will be able too...
| Outcome Topic | Directly Relates To... | |
|---|---|---|
| 1. | Identify an oxidation – reduction (redox) reaction based on changes in oxidation numbers across the chemical change. | You will need to know how to correctly assign oxidation numbers in order to do this. There is a callout box for Rules Assigning Oxidation Numbers on the gchem site. Go there and memorize those rules. Know how to implement those rules. |
| 2. | Identify oxidizing/reducing agents in chemical reaction. | After you know the oxidation numbers, you will know what is oxidized and what is reduced. The species that itself is oxidized is the reducing agent. The species that itself is reduced is the oxidizing agent. |
| 3. | Balance a net redox reaction using the ½ reaction method in acidic or basic solution. | Get the oxidation numbers first. Take the difference of those oxidation numbers to know the number of electrons for that particular 1/2 reaction. Then scale the two half reactions such that the total number of electrons matches. Balance out O's and H's with those specific sets of rules. |
| 4. | Recognize degrees of reactivity based on an activity series table or a standard reduction potential table. | Strongest oxidizing agents are on the LEFT side and have the greatest positive \({\cal E}^\circ\). The strongest reducing agents are on the RIGHT and have the greatest negative \({\cal E}^\circ\). |
| 5. | Apply standard reduction potential data to determine the relative strength of oxidizing/reducing agents. | This is really the same as #4. Why did we write this twice? Read what I said on #4. |
| 6. | Construct an electrochemical cell diagram, including identifying the anode, cathode, direction of electron flow, sign of the electrodes, direction of ion flow in salt bridge, from a redox reaction or from short hand cell notation. | There have been numerous examples of this very thing. Know what is shown in an actual diagram (beakers, U-tubes, electrodes, wires, voltmeters,...) AND what is implied as shown in the shorthand method (vertical bars between the variou phases). |
| 7. | Describe the standard hydrogen electrode and state it’s function. | Hmmmm. 1 M H+ with a platinum electrode in it. H2 gas is bubbled over it at 1 atm of pressure. It is our chosen standard. We picked 0.0000...forever as the voltage. It is zero at ALL temperatures for reference purposes. |
| 8. | Apply standard reduction potential data to calculate the standard cell potential for an electrochemical cell and from the sign of the potential predict if the cell is voltaic or electrolytic. | In general, if we show a negative potential cell (as it is written), it will not spontaneously run as written without external energy being provided. That generally means that if it is in fact running as written, then it must be an electrolytic cell and we have a power supply forcing it to run in the non-spontaneous direction. Of course, any cell with a positive potential as shown is a voltaic cell and will run as written without any "help". |
| 9. | Calculate the cell potential for a nonstandard cell. | Use the Nernst Equation: \({\cal E} = {\cal E}^\circ - (RT/nF)\ln Q\) |
| 10. | Describe fully the relationship between the free energy and the cell potential. | First and foremost, you MUST have a balanced chemical equation (1/2 or whole) as a reference point. Then and only then do you use: \(\Delta G = -nF{\cal E}\). |
| 11. | Describe fully the relationship between cell potential and the equilibrium constant. | Fully? well this equation is pretty much it: \(nF{\cal E}^\circ = RT\ln K\) |
| 12. | Explain thermodynamically the operation of a concentration cell, and be able to predict the concentration in the cell based on the cell potential. | Remember that both 1/2 reactions are identical they just run in opposite directions. This also means that ALL concentration cells have \({\cal E}^\circ = 0\) V. ALL the drive for the cell (potential) comes from the attempt to make the two different concentrations equal to each other. The two different concentrations are completely represented by \(Q\) in the Nernst equation. |
| 13. | Understand the relationship between charge delivered or produced and the amount of reactant used or product formed for both galvanic and electrolytic cells. filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler filler | This is simply an understanding of chemical stoichiometry. Layer on top of that stoichiometry the bridge of the faraday constant. One faraday is the amount of charge in one mole of electrons (96485 C). So you count charge with electricity (\(I\cdot t\)) in coulombs, and then you convert that charge to moles of electrons by dividing it by 96485 (F) to get you moles of electrons. Then, you are totally in the counting realm of chemistry with moles of things. Look at the balanced equation and solve for any part of it you want. |
| 14. | Describe the basic principles of battery design. | There is really quite a bit here. The main idea being to build a voltaic cell where the potential does not change much at all with use. Best way to achieve this is to try and use solids as your active materials. A solid will keep its activity of 1 even as it is depleted or increased. |
| 15. | Identify the differences and similarities of the three types of batteries. | Those 3 types would be (1) Primary Cells, (2) Secondary Cells, and (3) Fuel Cells. |
| 16. | Know the chemical reactions used in a lead-acid battery. | This is fully illustrated and shown on our gchem site in the section called Rechargeable Batteries. |
Know ALL necessary formulas for answering all the questions that go with the outcomes listed above.
There ARE many concepts that you must still know from chemical equilibrium and acid/base theory. In particular, still know how to correctly write out a mass action expression (Q or K) and how to calculate pH. Also still know the value for Kw at 25°C.