Download Experiment 26 Bishop Voltaic and Electrolytic Cells Objective

Experiment 26
Bishop
Voltaic and Electrolytic Cells
Objective:
• Observe a Voltaic and Electrolytic Cells.
• Determine where oxidation and reduction occurs in the different cells.
• Calculate the Standard cell voltage from each electrode cell.
Experiment:
Part A. Voltaic Cell – Spontaneous Reduction
Part B Electrolytic Cell – Non-Spontaneous Reduction
Anode
Oxidation
Anion migrate to the
anode
Electrons leave the cell
Negative in the voltaic
cell
Cathode
Reduction
Cations migrate to the
cathode
Electrode enters the cell
Negative in the
electrolytic cell.
Procedure: Work in pairs. It is doable alone it just takes longer.
Prepare your own U tube. You need to prepare a fresh one for each cell.
• Dissolve 0.25 grams of agar in 25 mL of NaNO3 at 90o C. Don't boil it.
• There must be no air bubbles at all.
• To discard, heat the U tube and collect the melted agar in a test tube. Let it
solidify before putting in the waste jar. Agar will clog the sinks.
Voltmeter
• Connect the leads according to color.
• Black lead goes into the COM
• Red lead goes into the V
• Set the meter to V---, starting at 2 and adjusting as necessary.
Part A:
Check-out a voltmeter, U-tube
Step 4. Iron II sulfate oxidizes readily and should be prepare immediately before use. To
make a 1 M solution, dissolve 2.3 gram in 10 mL of distilled water.
Step 8. Black is common and red goes to the DC voltage. The red terminal is positive.
Wash the electrodes, wipe dry and remove oxidation by lightly
sanding them. Return the electrodes to the original containers.
Tin electrodes might be too thin to reuse - they can be put in
the waste jar.
Part B
Check-out a power source, and electrode.
Step 26. Use a 12 well plate.
Step 27. Use well
A1
A4
C1
C4
Step 30. Use power source instead of the 9 volt battery for the electrolytic cell ( Figure
26.6) Use the alligator clips to connect to the electrode. Set the voltage to 9. Adjust the
polarity if voltage is negative.
Step 33. After repeating the process with KI use starch pellet instead of starch solution.
Step 34. Use a 100 mL beaker instead of a well plate.