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Phosphorus is a chemical element with the symbol P and the atomic number 15. All elemental forms of phosphorus are highly reactive and are therefore never found in nature. They can nevertheless be prepared artificially, the two most common ones being white phosphorus and red phosphorus.
A general formula for such cyclic compounds is [HPO 3] x where x = number of phosphoric units in the molecule. When metaphosphoric acids lose their hydrogens as H +, cyclic anions called metaphosphates are formed. An example of a compound with such an anion is sodium hexametaphosphate (Na 6 P 6 O 18), used as a sequestrant and a food additive.
Contrary to biology, biochemistry and biomedicine branches, in organic and inorganic chemistry branches, and in the branch of chemical nomenclature (see IUPAC), the correct name for the −P(=O)(−O −) 2 group is not "phosphoryl", but phosphonato, and the correct name for the −P(=O)(−OH) 2 group is phosphono, and the term phosphoryl ...
The most known chemical elements whose covalent combinations make up most biological molecules on Earth. [2] All of these elements are nonmetals . In animals in general, the four elements—C, H, N, and O—compose about 96% of the weight, and major minerals (macrominerals) and minor minerals (also called trace elements ) compose the remainder.
White phosphorus, yellow phosphorus or simply tetraphosphorus (P 4) exists as molecules of four phosphorus atoms in a tetrahedral structure, joined by six phosphorus—phosphorus single bonds. [1] The free P 4 molecule in the gas phase has a P-P bond length of r g = 2.1994(3) Å as was determined by gas electron diffraction . [ 2 ]
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
Pie charts of typical human body composition by percent of mass, and by percent of atomic composition (atomic percent) Body composition may be analyzed in various ways. This can be done in terms of the chemical elements present, or by molecular structure e.g., water , protein , fats (or lipids ), hydroxyapatite (in bones), carbohydrates (such ...
In organic chemistry, phosphate or orthophosphate is an organophosphate, an ester of orthophosphoric acid of the form PO 4 RR′R″ where one or more hydrogen atoms are replaced by organic groups. An example is trimethyl phosphate, (CH 3) 3 PO 4. The term also refers to the trivalent functional group OP(O −) 3 in such esters.