How to Produce Hydrogen From Water With Pulsed Electricity

Water is made of hydrogen and oxygen molecules and can be separated into these elements using electricity in a process known as electrolysis. Electrolysis of water can be done with either a constant flow of electricity or by pulsing the electricity through the water. Pulsing electricity will only produce small amounts of hydrogen and oxygen. For a more efficient yield, you will need professionally-produced equipment.

Things You'll Need

• Rectangular tank (e.g. fish tank)
• Copper wire
• 2 plastic containers/tumblers
• 9-volt square battery
• Match or splint

Instructions

Assembling the Water Electrolysis Tank

1. Fill a long, rectangular tank made of plastic or glass with water until it is about 1/2 to 3/4 full. Add a small amount of salt to the water, a teaspoon or two will be enough. This will help the electricity to conduct more efficiently. Mix the salt into the water until it is dissolved.

2. Make the electrodes using copper wire. This can be used straight off the roll. In order to make a current flow through the water, you will need two electrodes, one negative and one 'positive. Cut the wire to the desired length using scissors. Leave enough length on each wire so that you can attach them to the battery. The wire does not need to be twisted or shaped to form the electrodes.

3. Cover the middle of the tank with cardboard, leaving space at each end. This will seal in the produced gases, allowing you to collect them at each end.

4. Put one electrode into the water through the space at each end, so that they will be at opposite ends of the tank. Cover these spaces with the plastic tumblers or containers. These will collect the gases.

Attaching the Battery and Separating Hydrogen From Water

1. Pulse electricity through the water using the battery by twisting the end of each copper wire around the positive and negative connectors of the battery. These are the two round attachments at each end.

2. Control the length of the electrical pulses by attaching and detaching one of the electrode wires. This will break the circuit and stop the electricity from flowing. Bubbles in the water will indicate that the electrical circuit is working.

3. Pulse electricity through the water for several minutes. The water will separate into hydrogen and oxygen. The hydrogen will be collected in the container above the negative electrode, the wire attached to the negative battery attachment.

Tips & Warnings

• You can test that hydrogen has been produced by holding a lighted match or splint just inside this container. Hydrogen will cause the flame to make a pop sound.

• All steps should be supervised by an adult.

References

• California Energy Commission: H2O Electrolysis
• NASA Aquarius Education and Public Outreach: Electrolysis of Salt Water

Resources

• Sweet Briair College: H2O -- the Mystery, Art and Science of Water