How to Turn Water into Hydrogen

Test tubes are commonly used to collect gases during electrolysis.

Water, one of the most abundant resources on the planet, is composed of the gases oxygen and hydrogen. You can use electrolysis to separate the two gases. Electrolysis involves introducing an electric current into a small amount of water and collecting the two gases in separate containers, typically glass test tubes turned upside down. It is not a particular efficient process, as energy is lost as heat, and it will only produce a small amount of gas.

Things You'll Need

• 6-volt battery
• 2 copper wires, each 2 feet long, with an alligator clamp on one end
• 1 quart of water
• 2 100-milliliter test tubes
• 2 test tube clamps
• 2-quart bucket
• 3 tablespoons of salt

Instructions

1. Mount the test tube clamps to the side of the bucket. Add salt and water to the bucket and stir it until the salt dissolves.

2. Submerge both test tubes so that they fill up halfway with water; then turn them upside down and secure them to the test tube clamps. Make sure the open ends of the tubes are 3 or 4 inches below the surface.

3. Position the two wires through the water such that the ends are in the test tubes but still submerged. Try to position them so that the ends are right at the level of the test tube openings. Note which wire will be connected to the negative battery terminal.

4. Connect the other ends of the two copper wires to the battery terminals, using the alligator clamps.

5. Observe as hydrogen gas collects in the tube associated with the negative terminal. Oxygen will collect in the other test tube.

Tips & Warnings

• Substitute a few tablespoons of vinegar for salt.

References

• Georgia State University: Electrolysis of Water and Fuel Cell Operation
• Tutorvista: Electrolysis of Water Science
• Worley School: Simple Electrolysis of Water