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  2. Calcium peroxide - Wikipedia

    en.wikipedia.org/wiki/Calcium_peroxide

    Calcium peroxide or calcium dioxide is the inorganic compound with the formula CaO 2. It is the peroxide (O 2 2−) salt of Ca 2+. Commercial samples can be yellowish, but the pure compound is white. It is almost insoluble in water. [3]

  3. Photosystem II - Wikipedia

    en.wikipedia.org/wiki/Photosystem_II

    The oxygen-evolving complex is the site of water oxidation. It is a metallo-oxo cluster comprising four manganese ions (in oxidation states ranging from +3 to +4) [6] and one divalent calcium ion. When it oxidizes water, producing oxygen gas and protons, it sequentially delivers the four electrons from water to a tyrosine (D1-Y161) sidechain ...

  4. Heterogeneous water oxidation - Wikipedia

    en.wikipedia.org/wiki/Heterogeneous_Water_Oxidation

    Reduction 4H + + 4e − → 2H 2 E° = 0.00 V vs. NHE Overall 2H 2 O → 2H 2 + O 2 E°cell = +1.23 V; ΔG = 475 kJ/mol . Water splitting can be done at higher pH values as well however the standard potentials will vary according to the Nernst equation and therefore shift by -59 mV for each pH unit increase. However, the total cell potential ...

  5. Oxygen-evolving complex - Wikipedia

    en.wikipedia.org/wiki/Oxygen-evolving_complex

    Photons trapped by photosystem II move the system from state S 0 to S 1 to S 2 to S 3 and finally to S 4. S 4 reacts with water producing free oxygen: 2 H 2 O → O 2 + 4 H + + 4 e −. This conversion resets the catalyst to the S 0 state. The active site of the OEC consists of a cluster of manganese and calcium with the formula Mn 4 Ca 1 O x ...

  6. Water oxidation catalysis - Wikipedia

    en.wikipedia.org/wiki/Water_oxidation_catalysis

    The intermediate formed reacts with water to liberate O 2. The cobalt-polyoxometalate complex [Co 4 (H 2 O) 2 (α-PW 9 O 34) 2] 10− is highly efficient WOC. [11] Some iron complexes catalyze water oxidation. A water-soluble complex [Fe(OTf) 2 (Me 2 Pytacn)] (Pytacn=pyridine-substituted trimethyltriazacyclononane; OTf= triflate) is an ...

  7. Oxidation state - Wikipedia

    en.wikipedia.org/wiki/Oxidation_state

    In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to other atoms were fully ionic. It describes the degree of oxidation (loss of electrons ) of an atom in a chemical compound .

  8. Stoichiometry - Wikipedia

    en.wikipedia.org/wiki/Stoichiometry

    Reaction stoichiometry describes the 2:1:2 ratio of hydrogen, oxygen, and water molecules in the above equation. The molar ratio allows for conversion between moles of one substance and moles of another. For example, in the reaction 2 CH 3 OH + 3 O 22 CO 2 + 4 H 2 O. the amount of water that will be produced by the combustion of 0.27 moles ...

  9. Oxygen compounds - Wikipedia

    en.wikipedia.org/wiki/Oxygen_compounds

    2). [6] These compounds form by oxidation of alkali metals with larger ionic radii (K, Rb, Cs). For example, potassium superoxide (KO 2) is an orange-yellow solid formed when potassium reacts with oxygen. Hydrogen peroxide (H 2 O 2) can be produced by passing a volume of 96% to 98% hydrogen and 2 to 4% oxygen through an electric discharge. [7]