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Date: 23-9-2020
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Date: 29-9-2020
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Date: 2-8-2019
1259
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The difference in oxidation states between nitrogen and phosphorus is less pronounced than between oxygen and sulfur. Organophosphorus compounds having phosphorus oxidation states ranging from –3 to +5, as shown in the following table, are well known (some simple inorganic compounds are displayed in green). As in the case of sulfur, the P=O double bonds drawn in some of the formulas do not consist of the customary sigma & pi-orbitals found in carbon double bonds. Phosphorus is a third row element, and has five empty 2d-orbitals that may be used for p-d bonding in a fashion similar to p-p (π) bonding. In this way phosphorus may expand an argon-like valence shell octet by two electrons (e.g. phosphine oxides).
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