GC: n
CT: Hydrogen is the simplest element. An atom of hydrogen consists of only one proton and one electron. It’s also the most plentiful element in the universe. Despite its simplicity and abundance, hydrogen doesn’t occur naturally as a gas on the Earth – it’s always combined with other elements. Water, for example, is a combination of hydrogen and oxygen (H2O).
Hydrogen is also found in many organic compounds, notably the hydrocarbons that make up many of our fuels, such as gasoline, natural gas, methanol, and propane. Hydrogen can be separated from hydrocarbons through the application of heat – a process known as reforming. Currently, most hydrogen is made this way from natural gas. An electrical current can also be used to separate water into its components of oxygen and hydrogen. This process is known as electrolysis. Some algae and bacteria, using sunlight as their energy source, even give off hydrogen under certain conditions.
Hydrogen is high in energy, yet an engine that burns pure hydrogen produces almost no pollution. NASA has used liquid hydrogen since the 1970s to propel the space shuttle and other rockets into orbit. Hydrogen fuel cells power the shuttle’s electrical systems, producing a clean byproduct – pure water, which the crew drinks.
A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. Fuel cells are often compared to batteries. Both convert the energy produced by a chemical reaction into usable electric power. However, the fuel cell will produce electricity as long as fuel (hydrogen) is supplied, never losing its charge.
S: http://www.renewableenergyworld.com/rea/tech/hydrogen (last access: 20 December 2014)
N: 1. 1791, from French hydrogène, coined 1787 by G. de Morveau, Lavoisier, Berthollet, and Fourcroy from Greek hydr-, stem of hydor “water” + French -gène “producing”. So called because it forms water when exposed to oxygen. Nativized in Russian as vodorod; in German, it is wasserstoff, “water-stuff.” An earlier name for it in English was Cavendish’s inflammable air (1767). Hydrogen bomb first recorded 1947; shortened form H-bomb is from 1950.
2. Element of atomic number 1. The lightest element and the most abundant element. Colorless gas; highly flammable. Density 0.0899 g/l; sp.gr 0.0694 referred to air; sp. volume 193 cu ft/lb (70 °F); m. p. -259 °F. Flammable limits in air 4-75% by volume. Very slightly soluble in water, alcohol, ether.
Atomic weight 1.008. A colourless, odourless, tasteless gas.
A gas formed of the single element hydrogen.
3. It is considered one of the most active gases.
When combined with oxygen, it forms a very clean flame which, however, does not produce a very high temperature or very much heat.
4. Cultural Interrelation: The explosion of the luxury airship Hindenburg at Lakehurst, NJ on May 6, 1937, serves as one of the most spectacular moments recorded by the media. But knowing the actual nature of the Hindenburg disaster, as well as knowing the behavior of hydrogen allows us to dispel this stigma associated with hydrogen.
S: 1. OED – http://www.etymonline.com/index.php?allowed_in_frame=0&search=hydrogen&searchmode=none (last access: 20 December 2014). 2 & 3. GDT (last access: 20 December 2014). 4. http://heshydrogen.com/the-hindenburg-myth/ (last access: 16 September 2016).
SYN: H, H2.
S: GDT (last access: 20 December 2014)
CR: blue hydrogen, green hydrogen, grey hydrogen, hydrogen refuelling station, hydrogenase, phosphate.
