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  2. Oxidation state - Wikipedia

    en.wikipedia.org/wiki/Oxidation_state

    The lowest oxidation state is −5, as for boron in Al 3 BC [3] and gallium in pentamagnesium digallide (Mg 5 Ga 2). In Stock nomenclature, which is commonly used for inorganic compounds, the oxidation state is represented by a Roman numeral placed after the element name inside parentheses or as a superscript after the element symbol, e.g. Iron ...

  3. Phosphorus - Wikipedia

    en.wikipedia.org/wiki/Phosphorus

    Phosphorus is a chemical element with the symbol P and the atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has an occurrence in the Earth's crust of about 0.1%, generally occurring as phosphate in ...

  4. Pnictogen - Wikipedia

    en.wikipedia.org/wiki/Pnictogen

    The Russell-Saunders term symbol of the ground state in all elements in the group is 4 S 3 ⁄ 2. The most important elements of this group to life on Earth are nitrogen (N), which in its diatomic form is the principal component of air, and phosphorus (P), which, like nitrogen, is essential to all known forms of life.

  5. Phosphonium - Wikipedia

    en.wikipedia.org/wiki/Phosphonium

    The Michaelis–Arbuzov reaction is the chemical reaction of a trivalent phosphorus ester with an alkyl halide to form a pentavalent phosphorus species and another alkyl halide. Commonly, the phosphorus substrate is a phosphite ester (P(OR) 3) and the alkylating agent is an alkyl iodide. [11] The mechanism of the Michaelis–Arbuzov reaction

  6. Phosphoric acids and phosphates - Wikipedia

    en.wikipedia.org/wiki/Phosphoric_acids_and...

    The general formula of a phosphoric acid is H n−2x+2 P n O 3n−x+1, where n is the number of phosphorus atoms and x is the number of fundamental cycles in the molecule's structure; that is, the minimum number of bonds that would have to be broken to eliminate all cycles.

  7. Phosphoryl group - Wikipedia

    en.wikipedia.org/wiki/Phosphoryl_group

    A phosphoryl group is a trivalent >P(=O)− group, consisting of a phosphorus atom (symbol P) and an oxygen atom (symbol O), where the three free valencies are on the phosphorus atom. While commonly depicted as possessing a double bond (P=O) the bonding is in fact non-classical. [1]

  8. State of matter - Wikipedia

    en.wikipedia.org/wiki/State_of_matter

    The term phase is sometimes used as a synonym for state of matter, but it is possible for a single compound to form different phases that are in the same state of matter. For example, ice is the solid state of water, but there are multiple phases of ice with different crystal structures , which are formed at different pressures and temperatures.

  9. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    Phosphorus and sulfur are also common essential elements, essential to the structure of nucleic acids and amino acids, respectively. Chlorine, potassium, magnesium, calcium and phosphorus have important roles due to their ready ionization and utility in regulating membrane activity and osmotic potential. [2]