Lesson 9: Objectives
Purpose:
To study reactions which involve the transfer of electrons.
Objectives:
You have completed this lesson when you can:
1. Describe what happens when an electric current is passed through water, an aqueous solution, or a molten salt.
2. Name the electrodes used in electrolysis. Name and describe the reactions that take place at each electrode. Write equations for those reactions.
3. Describe the process of electroplating. Write equations for the reactions that occur in electroplating.
4. Describe the relationship between current, time and amount of chemicals reacting in electrolytic cells.
5. Define or describe oxidation-reduction reactions, recognize examples, and explain why oxidation and reduction must occur at the same time.
6. Given a redox reaction (equation, description or the real thing), determine which chemicals are:
a. the oxidizing agent.
b. the reducing agent.
c. being oxidized.
d. being reduced.
e. have been oxidized.
f. have been reduced.
7. Determine which of two chemicals will be more easily oxidized (or reduced), either from trends on the periodic table or from information on an experiment involving the two elements or from a standard oxidation potential (SOP) list.
8. Use a standard oxidation potential (SOP) list to:
a. determine which of several substances has the greatest tendency to be oxidized or reduced.
b. identify the oxidized and reduced forms of chemicals.
c. determine which oxidation-reduction reactions will occur.
d. calculate the voltage of a voltaic cell.
9. Describe voltaic cells:
a. explain how oxidation-reduction reactions can be used to produce electricity.
b. identify anode, cathode, and salt bridge; describe their functions.
c. describe the flow of electricity.
d. explain what happens to the chemicals involved for a given oxidation-reduction reaction.
e. explain why the voltage will probably not be what is calculated from an SOP list.
10. List and describe a few important biological processes that consist of oxidation-reduction reactions.
11. List and describe methods that can be used to protect chemicals (and things made of them) from oxidation.
Assignments:
Outside Reading (optional): Find the chapter or sections in your text that deal with the following topics and read them.
Electrochemistry
Oxidation-Reduction (Redox) Reactions
Electrolytic Cells
Voltaic Cells
To be turned in:
Lab report - Activity of Metals and Ions (you may hand in the pages from the workbook, as long as your writing is legible; if it is not, please type your report)
Problem set