enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Nitrogen - Wikipedia

    en.wikipedia.org/wiki/Nitrogen

    Nitrogen is commonly used during sample preparation in chemical analysis. It is used to concentrate and reduce the volume of liquid samples. Directing a pressurised stream of nitrogen gas perpendicular to the surface of the liquid causes the solvent to evaporate while leaving the solute(s) and un-evaporated solvent behind. [89]

  3. Pnictogen - Wikipedia

    en.wikipedia.org/wiki/Pnictogen

    Liquid nitrogen is a commonly used cryogenic liquid. [12] Nitrogen in the form of ammonia is a nutrient critical to most plants' survival. [12] Synthesis of ammonia accounts for about 1–2% of the world's energy consumption and the majority of reduced nitrogen in food. Phosphorus is used in matches and incendiary bombs. [12]

  4. Nitrogen compounds - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_compounds

    The chemical element nitrogen is one of the most abundant elements in the universe and can form many compounds. It can take several oxidation states; but the most common oxidation states are -3 and +3. Nitrogen can form nitride and nitrate ions. It also forms a part of nitric acid and nitrate salts.

  5. Liquid nitrogen - Wikipedia

    en.wikipedia.org/wiki/Liquid_nitrogen

    Nitrogen is odorless, colorless, and tasteless and may produce asphyxia without any sensation or prior warning. [20] [21] [22] Oxygen sensors are sometimes used as a safety precaution when working with liquid nitrogen to alert workers of gas spills into a confined space. [23] Vessels containing liquid nitrogen can condense oxygen from air. The ...

  6. Solid nitrogen - Wikipedia

    en.wikipedia.org/wiki/Solid_nitrogen

    Solid nitrogen is a number of solid forms of the element nitrogen, first observed in 1884. Solid nitrogen is mainly the subject of academic research, but low-temperature, low-pressure solid nitrogen is a substantial component of bodies in the outer Solar System and high-temperature, high-pressure solid nitrogen is a powerful explosive, with ...

  7. Nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Nitrogen_cycle

    Nitrogen is present in the environment in a wide variety of chemical forms including organic nitrogen, ammonium (NH + 4), nitrite (NO − 2), nitrate (NO − 3), nitrous oxide (N 2 O), nitric oxide (NO) or inorganic nitrogen gas (N 2). Organic nitrogen may be in the form of a living organism, humus or in the intermediate products of organic ...

  8. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]

  9. Isotopes of nitrogen - Wikipedia

    en.wikipedia.org/wiki/Isotopes_of_nitrogen

    Nitrogen-15 is frequently used in NMR (Nitrogen-15 NMR spectroscopy). Unlike the more abundant nitrogen-14, which has an integer nuclear spin and thus a quadrupole moment, 15 N has a fractional nuclear spin of one-half, which offers advantages for NMR such as narrower line width. Nitrogen-15 tracing is a technique used to study the nitrogen cycle.