What is the chemical name of hydrogen

Information about the element: hydrogen

Symbol: H

International name (IUPAC): Hydrogen

Origin: Hydrogen is the most common chemical element in the universe, but not in the earth's crust. It is part of water and most organic compounds; in particular it occurs in all living organisms.

Importance: hydrogenium = water generator

Period: 1

Group: 1 (I A)

Group name: Alkali metals

Oxidation number: 1 (-1)

Atomic mass [u]: 1,0079

Electronegativity (according to Allred): 2,2

Electronegativity (according to Pauling): 2,20

Physical state (20 ° C): gaseous

Density [g / cm2]: 0,00008988

Radioative: n

Melting temperature [° C]: -258,95

Boiling temperature [° C]: -252,87

Crystal structure: hexagonal

Every year more than 600 billion cubic meters of hydrogen (around 30 million t) are produced worldwide for countless applications in industry and technology. Important areas of application are:

  • Energy carrier: When welding, as rocket fuel. Hydrogen can also be used as fuel for jet engines or internal combustion engines - this method is technologically easier to implement in the short term and is the only option, especially for commercial vehicles with high mileage due to the lack of stability of the fuel cells, see hydrogen drive.
  • Reducing agent: H2 can react with metal oxides and thereby deprive them of oxygen. The result is water and the reduced metal. The process is used in the smelting of metallic ores, in particular to extract metals as pure as possible.
  • Fertilizer: With the (Haber-Bosch process), ammonia is produced from nitrogen and hydrogen and important fertilizers and explosives are produced from it.
  • Carbohydrate: Through various chemical reactions, coal is formed with H.2 converted into liquid hydrocarbons. In this way, petrol, diesel and heating oil can be produced artificially. At the moment, the process is of little economic importance because of its higher costs. But that could change drastically once the earth's oil supplies run out.
  • Fat hardening: Hardened fat is often obtained from vegetable oil by means of hydrogenation, which can result in so-called trans fatty acids. The main reaction, however, is that the double bonds in the fatty acid chains of the fat molecules are saturated with hydrogen. The resulting molecules have a higher melting point, which makes the product solid. This is how you make margarine.
  • Coolant: Due to its high heat capacity, hydrogen is used as a coolant in power plants and industrial plants. In particular, one sets H2 where liquid cooling can be problematic. The heat capacity comes into play where the gas cannot circulate or can only circulate slowly. Because the thermal conductivity is also high, flowing H is used2 also for the transport of thermal energy into large reservoirs (e.g. rivers). In these applications, hydrogen protects the systems from overheating and increases efficiency.
  • Cryogenic: Because of its high heat capacity, liquid hydrogen is suitable as a cryogen, i.e. as a coolant for extremely low temperatures. Even larger amounts of heat can be absorbed well by liquid hydrogen before a noticeable increase in its temperature occurs. In this way, the low temperature is maintained even with external fluctuations.
  • Lifting gas: Hydrogen was first used in balloons and airships. Because of the high flammability of H2-Air mixtures, however, this repeatedly led to accidents. The greatest catastrophe in this context is probably the disaster of 1923, the most famous one in 1937. Hydrogen as a lifting gas has meanwhile been replaced by helium and only fulfills this purpose in very special applications.

Occurrence: Hydrogen is the most common chemical element in the sun and the large gas planets Jupiter, Saturn, Uranus and Neptune, which combine over 99.99% of the mass of the solar system. An even higher proportion of hydrogen is assumed to exist in the entire universe (ignoring dark matter). Hydrogen makes up 75% of the total mass, or 93% of all atoms in the solar system. On earth, the mass fraction is much lower, based on the total weight about 0.12%, based on the earth's crust 2.9%. In addition - in contrast to the occurrences in space - the terrestrial hydrogen is mainly bound and almost never pure (i.e. as an unmixed gas). No other element is known to have so many compounds; the most common is water.

Frequency: 0.88% (percentage by mass of the earth's shell, i.e. the earth's crust / oceans up to 16 km depth)

Discovery: 1766

Discoverer: Henry Cavendish

  • Protium: 1H (no neutron)
  • deuterium: 2H (one neutron)
  • Tritium: 3H (two neutrons)