Hydrogen

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Hydrogen is a chemical element. It is one type of atom. Atoms are tiny, and everything that exists is made of atoms. It is the simplest atom in the Universe. Its symbol in science is H. Scientists give atoms an atomic number, and the number for hydrogen is 1. Hydrogen is most commonly found on Earth as a gas, or as part of water. Water is made of hydrogen and oxygen.

Hydrogen is normally found in groups of two atoms. This means it is diatomic. Hydrogen will have a chemical reaction when mixed with most other elements. It has no color nor smell.

It is:

  • A gas at room temperature
  • A non-metal
  • The lightest of all the elements in the periodic table
  • The lightest element in the Universe
  • The most common element in the Universe

However, hydrogen is very uncommon in the Earth's atmosphere. It is mostly found in water (where it is combined with oxygen) and in all organic compounds and living things. Hydrocarbons, like fossil fuels, are compounds where hydrogen is combined with carbon.

The name "hydrogen" comes from the Greek word for water, 'υδορ (pronounced /HEEW-dor/).

[edit] Hydrogen as fuel (fusion)

From a physics point of view, hydrogen has one proton, and its variants, deuterium and tritium, also have neutrons.

Nuclear fusion relies on forcing hydrogen atoms together to make helium and energy, exactly as happens in a star like the Sun, or in a hydrogen bomb. This needs a large amount of energy to get started, and is not easy to do yet. A big advantage over nuclear fission is that no waste is produced, and no toxic fuel like uranium is needed. There is a lot of deuterium in seawater.

[edit] Burning hydrogen

Electricity, as a flow of electrons through a conductor, can be easily converted to hydrogen by "adding a proton", to make a flow of hydrogen atoms instead. This does not lose the energy as it is moved around, although it still takes energy to do that - and when the hydrogen is burned in a fuel cell, which combines it with oxygen, the only emission is totally pure water.

Hydrogen is also used as a fuel in space travel.

[edit] Hydrogen power grid

For these reasons, many people believe hydro power will eventually replace technologies such as diesel-electric engines and biodiesel fuel. These do not require totally new engines and filling stations, as does the hydrogen infrastructure. Also, there must be electricity to charge the fuel cell by creating the hydrogen.

So, it is not correct to see hydrogen as a fuel as it is in fusion, if it is stored in a fuel cell. It is more of a replacement for the power grid. Such a grid and infrastructure with new vehicles might be first made in Iceland, a country that has much free geothermal energy and is quite small. Because it imports all fossil fuel, it would help Iceland to completely stop using it.