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  • atom
  • As the only neutral atom for which the Schrödinger equation can be solved analytically, study of the energetics and bonding of the hydrogen atom has played a key role in the development of quantum mechanics . (wikipedia.org)
  • The ground state energy level of the electron in a hydrogen atom is −13.6 eV, which is equivalent to an ultraviolet photon of roughly 91 nm wavelength. (wikipedia.org)
  • The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, which conceptualizes the electron as "orbiting" the proton in analogy to the Earth's orbit of the Sun. However, the atomic electron and proton are held together by electromagnetic force, while planets and celestial objects are held by gravity. (wikipedia.org)
  • A more accurate description of the hydrogen atom comes from a purely quantum mechanical treatment that uses the Schrödinger equation, Dirac equation or even the Feynman path integral formulation to calculate the probability density of the electron around the proton. (wikipedia.org)
  • CH4 + H2O → CO + 3 H2 In a second stage, additional hydrogen is generated through the lower-temperature, exothermic, water gas shift reaction, performed at about 360 °C: CO + H2O → CO2 + H2 Essentially, the oxygen (O) atom is stripped from the additional water (steam) to oxidize CO to CO2. (wikipedia.org)
  • gases
  • Depending on the quality of the feedstock (natural gas, rich gases, naphtha, etc.), one ton of hydrogen produced will also produce 9 to 12 tons of CO2. (wikipedia.org)
  • carbon black
  • Further, if soaked in liquid oxygen, some materials such as coal briquettes, carbon black, etc., can detonate unpredictably from sources of ignition such as flames, sparks or impact from light blows. (wikipedia.org)
  • occurs
  • Dibenzothiophene (see drawing), a tricyclic heterocycle consisting of two benzene rings fused to a central thiophene ring occurs widely in heavier fractions of petroleum, along with its alkyl substituted derivatives. (wikipedia.org)
  • substance
  • Its monatomic form (H) is the most abundant chemical substance in the Universe , constituting roughly 75% of all baryonic mass. [note Non- remnant stars are mainly composed of hydrogen in the plasma state . (wikipedia.org)
  • liquid
  • Liquid oxygen has a pale blue color and is strongly paramagnetic: it can be suspended between the poles of a powerful horseshoe magnet. (wikipedia.org)
  • Liquid oxygen has an expansion ratio of 1:861 under 1 standard atmosphere (100 kPa) and 20 °C (68 °F), and because of this, it is used in some commercial and military aircraft as transportable source of breathing oxygen. (wikipedia.org)
  • Because of its cryogenic nature, liquid oxygen can cause the materials it touches to become extremely brittle. (wikipedia.org)
  • The tetraoxygen molecule (O4) was first predicted in 1924 by Gilbert N. Lewis, who proposed it to explain why liquid oxygen defied Curie's law. (wikipedia.org)
  • Liquid oxygen is a common cryogenic liquid oxidizer propellant for spacecraft rocket applications, usually in combination with liquid hydrogen, kerosene or methane. (wikipedia.org)
  • Liquid oxygen is useful in this role because it creates a high specific impulse. (wikipedia.org)
  • Liquid oxygen was also used in some early ICBMs, although more modern ICBMs do not use liquid oxygen because its cryogenic properties and need for regular replenishment to replace boiloff make it harder to maintain and launch quickly. (wikipedia.org)
  • Many modern rockets use liquid oxygen, including the main engines on the now-retired Space Shuttle. (wikipedia.org)
  • The first measurable quantity of liquid oxygen was produced by Polish professors Zygmunt Wróblewski and Karol Olszewski (Jagiellonian University in Kraków) on April 5, 1883. (wikipedia.org)
  • Noncollinear magnetism in liquid oxygen: A first-principles molecular dynamics study" (PDF). (wikipedia.org)
  • however, there are several types, such as hydrogen fuel (for automotive uses), which are also categorized as a liquid fuel. (absoluteastronomy.com)
  • Gasoline is the most widely used liquid fuel. (absoluteastronomy.com)
  • global
  • Determination of rates of microbial activity is essential for evaluating the impact of crustal biosphere microbial activity on global elemental budgets and for understanding the mechanisms for growth and survival of life in this environment. (frontiersin.org)
  • Main
  • The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F). Pure hydrogen-oxygen flames emit ultraviolet light and with high oxygen mix are nearly invisible to the naked eye, as illustrated by the faint plume of the Space Shuttle Main Engine, compared to the highly visible plume of a Space Shuttle Solid Rocket Booster, which uses an ammonium perchlorate composite. (wikipedia.org)
  • elements
  • Sulfur is one of the core chemical elements needed for biochemical functioning and is an elemental macronutrient for all living organisms. (wikipedia.org)
  • common
  • The most common isotope of hydrogen, termed protium (name rarely used, symbol 1 H), has one proton and no neutrons . (wikipedia.org)
  • energy
  • The C−S bond dissociation energy for thiomethane is 89 kcal/mol (370 kJ/mol) compared to methane's 100 kcal/mol (420 kJ/mol) and when hydrogen is replaced by a methyl group the energy decreases to 73 kcal/mol (305 kJ/mol). (wikipedia.org)
  • reason
  • The reason for this difference is the higher electronegativity for oxygen drawing away electrons to itself at the expense of the aromatic ring current. (wikipedia.org)
  • organisms
  • Transforming atmospheric N2 into molecules that can be incorporated by most organisms (N2 fixation) is either done by microorganisms or through energetically costly chemical processes (lightning strikes, Haber- Bosch (H-B) process). (uantwerpen.be)
  • Sulfur is one of the core chemical elements needed for biochemical functioning and is an elemental macronutrient for all living organisms. (wikipedia.org)
  • high
  • The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F). Pure hydrogen-oxygen flames emit ultraviolet light and with high oxygen mix are nearly invisible to the naked eye, as illustrated by the faint plume of the Space Shuttle Main Engine, compared to the highly visible plume of a Space Shuttle Solid Rocket Booster, which uses an ammonium perchlorate composite. (wikipedia.org)
  • commercial
  • Its commercial uses are primarily in fertilizers , but it is also widely used in gunpowder , matches, insecticides and fungicides. (chemeurope.com)
  • cause
  • The destruction of the Hindenburg airship was a notorious example of hydrogen combustion and the cause is still debated. (wikipedia.org)
  • Storage
  • Hydrogen is a concern in metallurgy as it can embrittle many metals, complicating the design of pipelines and storage tanks. (wikipedia.org)