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  2. Thiophene - Wikipedia

    en.wikipedia.org/wiki/Thiophene

    Thiophene is considered to be aromatic, although theoretical calculations suggest that the degree of aromaticity is less than that of benzene. The "electron pairs" on sulfur are significantly delocalized in the pi electron system. As a consequence of its aromaticity, thiophene does not exhibit the properties seen for conventional sulfides. For ...

  3. Organic sulfide - Wikipedia

    en.wikipedia.org/wiki/Organic_sulfide

    A sulfide is similar to an ether except that it contains a sulfur atom in place of the oxygen. The grouping of oxygen and sulfur in the periodic table suggests that the chemical properties of ethers and sulfides are somewhat similar, though the extent to which this is true in practice varies depending on the application.

  4. Photoinitiator - Wikipedia

    en.wikipedia.org/wiki/Photoinitiator

    In the stratosphere, molecular oxygen (O 2) is an important photoinitiator that begins the ozone-production process in the ozone layer. Oxygen can be photolyzed into atomic oxygen by light with wavelength less than 240 nm. [3] O 2 → 2O. Atomic oxygen can then combine with more molecular oxygen to form ozone. O + O 2 → O 3

  5. Gas - Wikipedia

    en.wikipedia.org/wiki/Gas

    Drifting smoke particles indicate the movement of the surrounding gas.. Gas is one of the four fundamental states of matter.The others are solid, liquid, and plasma. [1] A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide).

  6. Heterocyclic compound - Wikipedia

    en.wikipedia.org/wiki/Heterocyclic_compound

    Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. [ 2 ] Examples of heterocyclic compounds include all of the nucleic acids , the majority of drugs, most biomass ( cellulose and related materials), and many natural and synthetic dyes.

  7. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 10 15 tonnes). [19] [70] [d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O 2 by volume) and Venus have much less. The O

  8. Polythiophene - Wikipedia

    en.wikipedia.org/wiki/Polythiophene

    A carbocation mechanism is inferred from the structure of 3-(4-octylphenyl)thiophene prepared from ferric chloride. [33] Polymerization of thiophene can be effected by a solution of ferric chloride in acetonitrile. The kinetics of thiophene polymerization also seemed to contradict the predictions of the radical polymerization mechanism. [63]

  9. Solid oxygen - Wikipedia

    en.wikipedia.org/wiki/Solid_oxygen

    Solid oxygen forms at normal atmospheric pressure at a temperature below 54.36 K (−218.79 °C, −361.82 °F). Solid oxygen O 2 , like liquid oxygen , is a clear substance with a light sky-blue color caused by absorption in the red part of the visible light spectrum.