1. Electrolysis of Water and Fuel Cells
Vanderbilt Student Volunteers for Science
Fall 2016

2. Conversions of Electrical Energy to Other Forms
Electrical Energy is Converted to:
Mechanical
Thermal
Light
Chemical
Sound
in these Examples
Motors
Heaters, toasters
Light bulbs
Electrolysis of water
Doorbells

3. A. Electrical Energy  Chemical Energy (Electrolysis)
Tell students to:
Attach the alligator clips from the 9-volt battery to the short end of the electrodes.
Submerge the electrodes in distilled water (sit lid on top of the jar).
Results
Distilled water cannot conduct electricity, so there is no reaction.

4. B. Electrical Energy  Chemical Energy – Electrolysis
Tell students to:
Remove the electrodes
Add 1 mini tsp sodium sulfate salt into jar of distilled water. Stir with toothpick.
Submerge the electrodes into the salt water.
Conclusion
Electrical energy comes from the battery.
The electric energy is converted into chemical energy to decompose water.
Water is decomposed into hydrogen and oxygen gases.
Only ionic solutions will conduct electricity.
Negative
Hydrogen gas bubbles
(2X as many)
Positive
Oxygen gas bubbles
Distilled water + sodium sulfate conducts electricity  Decomposition of water

5. C. Fuel Cell Fuel Cell Experiment
Students will work with a VSVS member. There are 4 sets of materials, so divide the class accordingly
A. Examining the Fuel Cell
B. Hydrogen Production
Students use the hand crank to produce hydrogen and oxygen gas, and observe the different volume each gas holds.
C. Fuel Cell Car
Students learn how the fuel cell car operates, and observe how the hydrogen is converted back to water.

6. Materials needed for each group
1 reversible fuel cell
1 model car
3oz bottle of distilled water
1 hand crank with built in patch cables
6 oz. cup
1 plastic plates

7. Activity A: Examining the fuel cell
Pass out the handout to the students
There is a student version and a volunteer version. The student version has an image of the fuel cell and the fuel cell car, along with numbers identifying the important parts of each. The volunteer version has more detailed descriptions of the identified parts
Help students identify all parts of the cell and the car

8. Activity A: Preparing the fuel cell
3. Place the fuel cell upside down on a
plastic plate placed on a flat surface
Remove the stoppers and set them
next to the fuel cell
5. Pour distilled water into both storage
cylinders until the water reaches the
tops of the small tubes in the center of
the cylinders
Be careful to pour the water around the outside of the cylinder, not into the small tube in the middle
Here
Not here

9. Activity A: Preparing the fuel cell
Tap fuel cell lightly to help water flow into the area surrounding the membrane and metal current-collecting plates
Add more water until it starts to overflow into the tubes in the cylinders
Place the stoppers back onto the cylinders. Make sure no air is trapped inside the cylinder. (However, small air bubbles will not cause problems.)
Turn the fuel cell right side up
This size of bubble is ok

10. Activity B: Hydrogen production
Attach the red cable from the hand crank to the banana jack positive terminal (red). Then attach the black cable from the hand crank to the banana jack negative terminal (black).
Rotate the hand crank (students may do this, but warned to do it carefully) to convert water into hydrogen and oxygen. Students should observe water displacing out of the outlet tube and into the open container above as gas bubbles form and collect in the storage cylinders
Water is displaced up here
Hydrogen gas collects here
Rotate the hand crank in full circles about 50 times (students may do this). They should be able to see a small bubble in the hydrogen tank.

11. Activity C: Fuel Cell Car
Detach the patch cables from the fuel cell
Being careful not to spill the overflow water, clip the fuel cell into the notches on the car
Place the car on the cup so that the wheels are touching neither the cup nor the ground

12. Activity C: Fuel Cell Car
Plug the cables from the car into the cell (red to red and black to black). The car will begin running as soon as both cables are plugged in.
Let the car run until it stops
Once the fuel is used up, have the students examine the two water tanks