Most of these items can easily be found around the home. Battery clips with end-attached alligator clamps can be found at electronics stores or superstores.
Sharpen the ends so that the graphite is well-exposed on both ends of each pencil.
Stir until the powder is fully dissolved. If you add salt, the reaction will be different than just electrolyzing pure water. As the molecules of water break apart, hydrogen gas will be formed, and oxygen will combine with the sodium ions to form hydroxyl ions and the chlorine in the salt will form a chlorine gas. (Please note that chlorine gas is highly toxic) If you add baking soda, the gases that form are hydrogen, oxygen, and carbon dioxide. [4] X Research source
Cut the cardboard so that it hangs over the top of the glass container with your mixture. Position it on top of the container so that the pencils dangle just above the bottom. Make sure the pencils are not touching each other.
It doesn’t matter which clamp you attach to which pencil.
The bubbles produced are bubbles of hydrogen and chlorine gas. The oxygen combines with the sodium to form hydroxyl ions and the remaining chlorine forms a gas.
You’ll also need the same supplies as above: 2 number 2 pencils, 9-volt battery, battery clip with alligator clamps, and water.
Position the pencils in the clamp so that the tips don’t touch the bottom of the container.
The oxygen atoms will combine with the sodium and available hydrogen ions to form sodium hydroxide.
It’s very important that no bubbles are present in the test tubes.
Remember the test tube needs to be completely full of water with no bubbles anywhere.
As the gas is produced, the water in the tube will be displaced and you will have a tube of pure hydrogen and chlorine gas or oxygen.
