Water is the most plentiful substance on earth, making up about 70 percent of our planet. Water is composed of hydrogen and oxygen molecules. Pure water is neutral, therefore it's a great insulator, however it's extremely rare, as virtually all water has some substance dissolved in it. The hydrogen and oxygen ions in water can be separated by passing an electric current through the water, which in turn will give it a temporary negative charge.
Pour water into a bowl. Use a glass, ceramic or wooden bowl.
Strip the wire. Take two pieces of insulated copper wire, about a foot long each, and strip the insulation off both ends with the scissors or a utility knife.
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Attach the wire to the battery. Take one of the wires and place one of the ends into one of the diodes on top of the battery. Tape it in place with electrical tape. Tape the other wire to the other diode.
Put the wires in the water. Set the 9-volt battery next to the bowl then drop the ends of the wires into the bowl and leave them there. After a while, bubbles will begin to form. It will take some time for the water to bubble up, and the water will have a negative charge as long as the bubbles are present.
Only touch the insulated part of the wires when connecting them to the battery and when dropping them into the water.