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  2. Synthetic element - Wikipedia

    en.wikipedia.org/wiki/Synthetic_element

    A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".

  3. Abiogenic petroleum origin - Wikipedia

    en.wikipedia.org/wiki/Abiogenic_petroleum_origin

    Hydrogen gas can be created by water reacting with silicates, quartz, and feldspar at temperatures in the range of 25 °C (77 °F) to 270 °C (518 °F). These minerals are common in crustal rocks such as granite. Hydrogen may react with dissolved carbon compounds in water to form methane and higher carbon compounds. [29]

  4. Chemical synthesis - Wikipedia

    en.wikipedia.org/wiki/Chemical_synthesis

    This requires mixing the compounds in a reaction vessel, such as a chemical reactor or a simple round-bottom flask. Many reactions require some form of processing ("work-up") or purification procedure to isolate the final product. [1] The amount produced by chemical synthesis is known as the reaction yield.

  5. Matter creation - Wikipedia

    en.wikipedia.org/wiki/Matter_creation

    It is possible to create all fundamental particles in the standard model, including quarks, leptons and bosons using photons of varying energies above some minimum threshold, whether directly (by pair production), or by decay of the intermediate particle (such as a W − boson decaying to form an electron and an electron-antineutrino).

  6. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. [1] When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change as new products are generated.

  7. Nucleosynthesis - Wikipedia

    en.wikipedia.org/wiki/Nucleosynthesis

    Star formation has been occurring continuously in galaxies since that time. The primordial nuclides were created by Big Bang nucleosynthesis, stellar nucleosynthesis, supernova nucleosynthesis, and by nucleosynthesis in exotic events such as neutron star collisions. Other nuclides, such as 40 Ar, formed later through radioactive decay. On Earth ...

  8. Chemical substance - Wikipedia

    en.wikipedia.org/wiki/Chemical_substance

    A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. [1] [2] Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combined without reacting, they may form a chemical mixture. [3]

  9. Matter - Wikipedia

    en.wikipedia.org/wiki/Matter

    A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. [13] [14] Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combined without reacting, they may form a chemical mixture. [15]