enow.com Web Search

Search results

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

    en.wikipedia.org/wiki/Permeation

    In physics and engineering, permeation (also called imbuing) is the penetration of a permeate (a fluid such as a liquid, gas, or vapor) through a solid.It is directly related to the concentration gradient of the permeate, a material's intrinsic permeability, and the materials' mass diffusivity. [1]

  3. Chlorofluorocarbon - Wikipedia

    en.wikipedia.org/wiki/Chlorofluorocarbon

    The rest of the unaccounted carbon bonds are occupied by chlorine atoms. The value of this equation is always a three figure number. An easy example is that of CFC-12, which gives: 90+12=102 -> 1 carbon, 0 hydrogens, 2 fluorine atoms, and hence 2 chlorine atoms resulting in CCl 2 F 2. The main advantage of this method of deducing the molecular ...

  4. Carbon - Wikipedia

    en.wikipedia.org/wiki/Carbon

    The simplest form of an organic molecule is the hydrocarbon—a large family of organic molecules that are composed of hydrogen atoms bonded to a chain of carbon atoms. A hydrocarbon backbone can be substituted by other atoms, known as heteroatoms .

  5. Permeability (materials science) - Wikipedia

    en.wikipedia.org/wiki/Permeability_(Materials...

    This may also be called the intrinsic permeability or specific permeability. These terms refer to the quality that the permeability value in question is an intensive property of the medium, not a spatial average of a heterogeneous block of material equation 2.28 [clarification needed] [further explanation needed]; and that it is a function of ...

  6. Carbon compounds - Wikipedia

    en.wikipedia.org/wiki/Carbon_compounds

    In general bonds of carbon with other elements are covalent bonds. Carbon is tetravalent but carbon free radicals and carbenes occur as short-lived intermediates. Ions of carbon are carbocations and carbanions are also short-lived. An important carbon property is catenation as the ability to form long carbon chains and rings. [3]

  7. Allotropy - Wikipedia

    en.wikipedia.org/wiki/Allotropy

    Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.

  8. Allotropes of carbon - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_carbon

    Likewise, under standard conditions, graphite is the most stable form of carbon. Therefore, it is used in thermochemistry as the standard state for defining the heat of formation of carbon compounds. Graphite conducts electricity, due to delocalization of the pi bond electrons above and below the planes of the carbon atoms. These electrons are ...

  9. Graphene - Wikipedia

    en.wikipedia.org/wiki/Graphene

    Graphene is the only form of carbon (or solid material) in which every atom is available for chemical reaction from two sides (due to the 2D structure). Atoms at the edges of a graphene sheet have special chemical reactivity. Graphene has the highest ratio of edge atoms of any allotrope. Defects within a sheet increase its chemical reactivity ...