How to Make Pure Oxygen

Water (H2O) consists of two small hydrogen atoms and one large oxygen atom.

Completely pure oxygen can be handy to have around for various reasons, ranging from combustion to breathing. Unfortunately, it can be both expensive and inconvenient to buy and keep on hand. Thankfully, with a little ingenuity, you can make pure oxygen right in your own home. Many times, you will already have all of the parts that are needed, so it won't cost you anything to build your oxygen-creation device. Better yet, it will only cost pennies in electricity each time you use it.

It is very difficult for anyone but a trained scientist to attempt separation of oxygen from the other gases in the air, so this guide will focus on obtaining pure oxygen from water.

Things You'll Need

• Table salt
• DC power source
• Funnel
• Balloon
• Duct tape

Instructions

1. Fill a container with water, and add salt to enhance conductivity. One-quarter cup of salt per gallon of water makes it much more conductive. Strip the ends of two wires so that at least 1/4 inch of bare wire is exposed; place them in the cup, ensuring they are at least several inches from each other. The two bare wires should not touch under any circumstances.

2. Attach one wire to the positive lead of any DC power source (preferably 12 volts) and the other wire to the negative lead. The more amperage the DC power source puts out, the faster gases will separated. Then turn on the power supply for a moment to test the unit. After a moment, the leads should begin bubbling. The positive wire will bubble with hydrogen gas, and the negative will bubble with oxygen.

3. Turn a funnel upside down and tape a normal balloon into place over its narrow end. Use duct tape to secure the balloon into place and keep it from popping off. (Before attaching the balloon, blow it up and deflate it several times in a row to wear out the material and reduce the resistance it provides.) You can now place the funnel into the water, upside down. If needed, use a small strip of duct tape to hold it into place, so the entire large end of the funnel stays submerged.

4. Place the negative wire directly under the funnel, so that when it bubbles and releases oxygen, the gas has no place to go but straight up, into the funnel and into the balloon. Make sure the hydrogen wire is located well away from the funnel, to ensure the oxygen isn't diluted. You may choose to harness the hydrogen gas as well, or simply let it escape into the atmosphere.

5. When the balloon has filled to the desired level, shut off the DC power source and tie the balloon. The balloon will now be filled with pure, 100 percent oxygen. Remember, balloon seals are far from perfect, and the oxygen will slowly leak out, so you will only have a short window of time in which to make use of this oxygen before the majority of it escapes from the balloon.

Tips & Warnings

• If you are making large amounts of hydrogen, consider taping a plastic bag (airtight) to the end of the funnel, which can unfold as it fills. A sandwich bag works great for small projects, whereas a garbage bag can be filled for bigger quantities.

• Only use DC power for this project. Both oxygen and hydrogen are highly combustible and potentially explosive, so keep them away from sparks or open flame.

Resources

• Wikipedia entry on H2O
• Electrolysis of water