Electrolysis of Water

Purpose:
To demonstrate the various forms of energy in the electrolysis of water and the recombination of H2 and O2.

Equipment:
12 volt car battery, rubber stoppered beaker with gas outlet, 2 carbon electrodes, salt water solution, rubber tube with eye dropper on end, dish of soapy water, plastic spoon, and matches.

Procedure:
Fill beaker half-full with salt solution. Place carbon electrodoes in rubber stopper and insert into beaker. Attach rubber tube to gas outlet of beaker and place eyedropper end in soapy water. Hook each carbon electrode to a battery terminal and watch for serious bubbling action. Let the bubbling continue for a few minutes or until a good supply of bubbles is formed in the soapy water. Scoop up a spoonful of bubbles and bring a lit match into their midst. The small explosions are evidence of heat energy that gas undergone numerous transformations.