When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Allotropy - Wikipedia

    en.wikipedia.org/wiki/Allotropy

    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.

  3. Allotropes of carbon - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_carbon

    These electrons are free to move, so are able to conduct electricity. However, the electricity is only conducted along the plane of the layers. In diamond, all four outer electrons of each carbon atom are 'localized' between the atoms in covalent bonding. The movement of electrons is restricted and diamond does not conduct an electric current.

  4. Allotropes of oxygen - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_oxygen

    Atomic oxygen, denoted O or O 1, is very reactive, as the individual atoms of oxygen tend to quickly bond with nearby molecules.Its lowest-energy electronic state is a spin triplet, designated by the term symbol 3 P.

  5. List of unsolved problems in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    Science. 309 (125th Anniversary). 1 July 2005. Unsolved Problems in Nanotechnology: Chemical Processing by Self-Assembly - Matthew Tirrell - Departments of Chemical Engineering and Materials, Materials Research Laboratory, California NanoSystems Institute, University of California, Santa Barbara [No doc at link, 20 Aug 2016]

  6. Inert-pair effect - Wikipedia

    en.wikipedia.org/wiki/Inert-pair_effect

    The inert-pair effect is the tendency of the two electrons in the outermost atomic s-orbital to remain unshared in compounds of post-transition metals.The term inert-pair effect is often used in relation to the increasing stability of oxidation states that are two less than the group valency for the heavier elements of groups 13, 14, 15 and 16.

  7. Allotropes of iron - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_iron

    Below 912 °C (1,674 °F), iron has a body-centered cubic (bcc) crystal structure and is known as α-iron or ferrite.It is thermodynamically stable and a fairly soft metal. α-Fe can be subjected to pressures up to ca. 15 GPa before transforming into a high-pressure form termed ε-Fe discussed below.

  8. Allotropes of plutonium - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_plutonium

    This makes plutonium very sensitive to changes in temperature, pressure, or chemistry, and allows for dramatic volume changes following phase transitions. [5] Unlike most materials, plutonium increases in density when it melts, by 2.5%, but the liquid metal exhibits a linear decrease in density with temperature. [6]

  9. Allotropes of phosphorus - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_phosphorus

    In 2006, the diatomic molecule was generated in homogeneous solution under normal conditions with the use of transition metal complexes (for example, tungsten and niobium). [ 41 ] Diphosphorus is the gaseous form of phosphorus , and the thermodynamically stable form between 1200 °C and 2000 °C.