Splitting the H2O (Water) Molecule

About: I am a 13 year old DIY hobbyist. I mainly focus on electronics, but I dabble in other ares as well.

Greetings. Today I will be showing the Instructables community how to do a very simple scientific demonstration. In this extraordinarily simple project, we will be splitting the water molecule en masse. Also, please take a few seconds to vote for me in the Water contest if you enjoyed this Instructable. Let us begin!

Step 1: The Science

As we all learned in 5th grade, water is made of three small particles called atoms. There are two Hydrogen atoms and one Oxygen atom. Together they make up water, or as chemists know it, dihydrogen monoxide- H₂O. Remember 5th grade science class? There you probably learned about things that atoms are made of, called subatomic particles. Subatomic particles include, but are not limited to, Protons, Neutrons, and Electrons. That last one, Electron, is what we are concerned with today. The Hydrogen and Oxygen atoms are held in what is known as a covalent bond. In a covalent bond, the two atoms, in this case Hydrogen and Oxygen, share an electron (picture above). So if we want to break up that relationship, we just have to give each side what it wants- and electron. A flow of electrons is called electricity. And since there are 1.00368e+25 molecules in a 300 milliliter glass of water, we need a lot of electrons...

*Side note- we need to add salt to the water to give it ions (charged atoms), which increase conductivity.

Step 2: Materials

Material List:

  • 250mL Water
  • 1 Tsp Salt, Preferably not Iodised
  • 9v Battery
  • 9v Battery Clip
  • Wire

Step 3: Do the Experiment

First, mix the salt in with the water. Now connect the wire to the 9v battery clip, and put the clip on the battery.Submerse the wires into the water and voila- you are splitting the water molecule. More Science: the bubbles you see on the negative wire are hydrogen bubbles. There are also oxygen bubbles coming from the positive one, but there are 1/2 as much, so they are nearly invisible. There is a video above.



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    3 Discussions


    5 months ago

    It's wery nice, make electrolise.
    Interesting notation about graphite rods, with this electrods you loose some oxygen. Because graphyte is carbon, and in result you have hidrogen, oxygen and carbon dioxide. Hidrogen is little bit more then you need for reactoin with oxygen.
    I use graphite from used butturies when I was a student :)


    5 months ago on Step 3

    When I was school student I made a lot of Oxygen and Hydrogen by spliting water.

    And I make a lot of explosions.

    Actual, for better reactions you need the battary acid (acumulator acid, low concentration of sulfuric acid ), lead (Pb) for electrods. And powerphool power block, I build for 24 v.
    Maybe later I will write some when I make this with my son.
    And you can grow in your experiment

    1 reply

    Reply 5 months ago

    Thank you for your suggestion. I considered using either graphite rods or lead for the electrodes, but wanted to keep this as cheap and simple as possible. Perhaps I will use lead sometime later, when I have thick gloves! (: