Making an Oxygen Generator

Water molecules contain oxygen and hydrogen.

Water is a miracle of creation. It is composed of the two most common elements in the universe---hydrogen and oxygen. According to Professor Jill Granger of Sweet Briar College, mixing one hydrogen atom and two oxygen atoms together produces water plus energy. Add energy to water and you separate the molecules to produce hydrogen and oxygen.



Do a simple electrolysis experiment at home to generate oxygen and hydrogen. You can use a solar cell or a battery and simple ingredients found at home to demonstrate how oxygen and hydrogen can be separated from water.

Things You'll Need

• Large glass measuring cup
• Aluminum foil potato wrap, 1 piece
• Battery snap connector, 9-volt
• 1/4 cup table salt
• 1 bottle distilled water
• Wooden spoon
• Scissors
• 9-volt battery
• Electrical tape

Instructions

1. Pour one cup of bottled water into the glass measuring cup and add the table salt to it. Stir with the wooden spoon until most of the salt is dissolved. The saline water is now an electrolyte solution.

2. Cut the potato wrap in half with scissors and accordion-fold the pieces to make two thick folded strips. The foil strips will be the anode and cathode for your electrolysis device.

3. Place the foil strips into the measuring cup, on opposite sides so that they can't touch each other. Fold the top of each foil strip down over the edge of the cup.

4. Strip one-half inch of insulation from each wire of the snap connector and attach the wires to the foil strips with a small piece of electrical tape.

5. Snap the connector onto the battery and observe the reaction between the foil strips and the salt water electrolyte. After a few minutes you will see bubbles forming on the ends of the foil strips. The current from the battery is causing the water molecules to separate. The oxygen atoms are attracted to foil attached to the positive terminal of the battery, and hydrogen atoms are drawn to the foil attached to the negative terminal.

Tips & Warnings

• Replace one of the foil strips with a piece of heavy copper wire and you have made a salt water battery.

• Disconnect the battery when you finish making your observations. Even though you are working with small amounts, you should remember that oxygen and hydrogen are flammable gases and use caution when working with them.

References

• Sweet Briar College: Chemistry of Water
• Northeast Sustainable Energy Association: Solar-Powered Electrolysis of Water and the Hydrogen Economy
• NASA: Aquarius: Electrolysis of Salt Water

Resources

• MIT News: 'Major discovery' from MIT primed to unleash solar revolution