Hello, this is Bing. I can help you with your question. Based on the information I found on the web, **H2** can be broken down into its two atoms of hydrogen (H) by supplying enough energy to overcome the bond that holds them together⁴. This process is called **dissociation** and requires an energy equal to or greater than the **dissociation energy** of H2, which is about 436 kJ/mol⁴.
One way to break down H2 is by using **electricity** to split water (H2O) into hydrogen (H2) and oxygen (O2) through a process called **electrolysis**¹. In this process, water is decomposed into its elements by passing an electric current through it. The electric current is provided by a battery or another source of electricity and the water needs to have an **electrolyte**, such as salt or acid, added to it to make it conductive¹. Two electrodes, usually made of metal or other conductive material, are inserted into the water and connected to the battery. The electrode connected to the positive terminal of the battery is called the **anode** and the one connected to the negative terminal is called the **cathode**¹. When the electric current flows through the water, hydrogen gas bubbles form at the cathode and oxygen gas bubbles form at the anode¹. The overall chemical reaction for electrolysis of water is:
2 H2O → 2 H2 + O2
Another way to break down H2 is by using **heat** to cause a reaction between hydrogen and oxygen that produces water and releases a large amount of energy. This reaction is called **combustion** or **oxidation** and can be ignited by a spark or a flame³. The reaction is very fast and explosive and can be dangerous if not controlled. The overall chemical reaction for combustion of hydrogen is:
2 H2 + O2 → 2 H2O
I hope this helps you understand how H2 can be broken down and what methods are used to do so.