Combustion is the scientific word for burning. In a combustion reaction a substance reacts with oxygen from the air and transfers energy to the surroundings as light and heat.
Fuel cells use hydrogen as a fuel. The reaction between hydrogen and oxygen is exothermic. This means that energy is given out. The hydrogen-oxygen fuel cell uses the energy released from the reaction to produce electrical energy efficiently.
To produce hydrogen, it must be separated from the other elements in the molecules where it occurs. There are many different sources of hydrogen and ways for producing it for use as a fuel. The two most common methods for producing hydrogen are steam-methane reforming and electrolysis (splitting water with electricity.
A: The chemical equation would be: H2 + O2 ⇌ H2O.
Hydrogen fuel is a zero carbon fuel burned with oxygen. It can be used in fuel cells or internal combustion engines (see HICEV). In a flame of pure hydrogen gas, burning in air, the hydrogen (H2) reacts with oxygen (O2) to form water (H2O) and releases energy.
Hydrogen is flammable, but oxygen is not. You can, however, break it down into hydrogen and oxygen by putting energy into it, in the form of an electric current. Watch out for sparks, though, or there will be a loud bang and a blue flame as the hydrogen and oxygen spontaneously recombine to form water again.
Hydrogen has a wide flammability range in comparison with all other fuels. As a result, hydrogen can be combusted in an internal combustion engine over a wide range of fuel-air mix- tures. A significant advantage of this is that hydrogen can run on a lean mixture.
While hydrogen has a high burn/explosive velocity, it has less explosive power than other fuel- air mixes. Except in extremely high concentrations, hydrogen is not toxic to humans. Hydrogen is odorless and tasteless.
The biggest reason why hydrogen-combustion engines are no good? They create nitrogen oxide, which isn't good for people or the environment. Even though carbon isn't part of the hydrogen combustion process, NOx isn't a compromise as automakers look to zero-emission vehicles.
Put more simply, it will take any engine that runs on diesel, gasoline, propane, or CNG and switch it over to run on 100 percent hydrogen. The hydrogen is passed through a membrane that strips it of any remaining oxygen or nitrogen, leaving pure hydrogen for the vehicle to burn.
Just mixing hydrogen and oxygen together doesn't make water – to join them together you need energy. The trouble with adding energy into the equation is that a large-scale chemical reaction of flammable hydrogen and oxygen (which is what keeps a fire burning) is likely to result in a rather large explosion.
Hydrogen can either be burned in a jet engine, or another kind of internal combustion engine, or can be used to power a fuel cell to generate electricity to power a propeller. Unlike most aircraft, which store fuel in the wings, hydrogen aircraft are usually designed with the hydrogen fuel tanks inside the fuselage.
Planes using hydrogen would emit only water, and initial tests suggest they can be just as fast as traditional planes, carrying more than a hundred passengers per flight over thousands of kilometres. A recent report on the potential of hydrogen-powered aviation said such planes could enter the market as soon as 2035.
