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  2. Oxygen reduction reaction - Wikipedia

    en.wikipedia.org/wiki/Oxygen_reduction_reaction

    Rather than combustion, organisms rely on elaborate sequences of electron-transfer reactions, often coupled to proton transfer. The direct reaction of O 2 with fuel is precluded by the oxygen reduction reaction, which produces water and adenosine triphosphate. Cytochrome c oxidase affects the oxygen reduction reaction by binding O 2 in a heme ...

  3. Heptane - Wikipedia

    en.wikipedia.org/wiki/Heptane

    Heptane or n-heptane is the straight-chain alkane with the chemical formula H 3 C(CH 2) 5 CH 3 or C 7 H 16. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 point is 100% iso-octane ).

  4. Heterogeneous water oxidation - Wikipedia

    en.wikipedia.org/wiki/Heterogeneous_Water_Oxidation

    Of the two half reactions, the oxidation step is the most demanding because it requires the coupling of 4 electron and proton transfers and the formation of an oxygen-oxygen bond. This process occurs naturally in plants photosystem II to provide protons and electrons for the photosynthesis process and release oxygen to the atmosphere, [ 1 ] as ...

  5. Stoichiometry - Wikipedia

    en.wikipedia.org/wiki/Stoichiometry

    This is illustrated in the image here, where the balanced equation is: CH 4 + 2 O 2 → CO 2 + 2 H 2 O. Here, one molecule of methane reacts with two molecules of oxygen gas to yield one molecule of carbon dioxide and two molecules of water. This particular chemical equation is an example of complete combustion. Stoichiometry measures these ...

  6. Spiroheptane - Wikipedia

    en.wikipedia.org/wiki/Spiroheptane

    The parent unsymmetrical member is spiro[2.4]heptane, which features cyclopropyl and cyclopentyl rings sharing one carbon. An early example of a spiro[3.3]heptane is the dicarboxylic acid C[(CH 2 ) 2 CH(CO 2 H)] 2 , also called Fecht's acid in honor of H. Fecht, of the Strasbourg Institute of Chemistry, the person who obtained this compound.

  7. Standard enthalpy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_formation

    For many substances, the formation reaction may be considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction can then be analyzed by applying Hess' law, which states that the sum of the enthalpy changes for a number of individual reaction steps equals the enthalpy change of the overall reaction.

  8. Oxygen evolution - Wikipedia

    en.wikipedia.org/wiki/Oxygen_evolution

    Oxygen evolution is the chemical process of generating elemental diatomic oxygen (O 2) by a chemical reaction, usually from water, the most abundant oxide compound in the universe. Oxygen evolution on Earth is effected by biotic oxygenic photosynthesis , photodissociation , hydroelectrolysis , and thermal decomposition of various oxides and ...

  9. Triplet oxygen - Wikipedia

    en.wikipedia.org/wiki/Triplet_oxygen

    Triplet oxygen, 3 O 2, refers to the S = 1 electronic ground state of molecular oxygen (dioxygen). Molecules of triplet oxygen contain two unpaired electrons, making triplet oxygen an unusual example of a stable and commonly encountered diradical : [ 2 ] it is more stable as a triplet than a singlet .