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Phosphorus has an oxidation number of −3 in phosphine. Phosphine is produced by hydrolysis of calcium phosphide, Ca 3 P 2. Unlike ammonia, phosphine is oxidised by air. Phosphine is also far less basic than ammonia. Other phosphines are known which contain chains of up to nine phosphorus atoms and have the formula P n H n+2. [31]
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.
Phosphorus comprises 0.1% by mass of the average rock [12] (while, for perspective, its typical concentration in vegetation is 0.03% to 0.2%), [13] and consequently there are quadrillions of tons of phosphorus in Earth's 3×10 19-ton crust, [14] albeit at predominantly lower concentration than the deposits counted as reserves, which are ...
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 ]
Diphosphenes, with the formula R 2 P 2, formally contain phosphorus-phosphorus double bonds. These phosphorus(I) species are rare but are stable provided that the organic substituents are large enough to prevent catenation. Bulky substituents also stabilize phosphorus radicals. Many mixed-valence compounds are known, e.g. the cage P 7 (CH 3) 3.
Phosphorus has a valence 3 in phosphine (PH 3) and a valence of 5 in phosphorus pentachloride (PCl 5), which shows that an element may exhibit more than one valence. The structural formula of a compound represents the connectivity of the atoms, with lines drawn between two atoms to represent bonds. [1]
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]
Examples: Calcium sulfide with strontium sulfide with bismuth as activator, (Ca,Sr)S:Bi, yields blue light with glow times up to 12 hours, red and orange are modifications of the zinc sulfide formula. Red color can be obtained from strontium sulfide.