phosphorus pentoxide

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Related to Phosphoric anhydride: pentoxide, Diphosphorus pentoxide

phosphorus pentoxide

n
(Elements & Compounds) a white odourless solid produced when phosphorus burns: has a strong affinity for water with which it forms phosphoric acids. Formula: P2O5 (commonly existing as the dimer P4O10). Also called: phosphoric anhydride
References in periodicals archive ?
Phosphorus is oxidized into phosphoric anhydride [P.sub.2][O.sub.5] according to the reaction
Phosphoric anhydride, which is characterized by rather strong acid properties at the temperature 1600[degrees]C, easily couples with iron oxide FeO with formation of phosphate 3FeO x [P.sub.2][O.sub.5].
Presence of free silica in slags destroys tetracalcium phosphate 4CaO x [P.sub.2][O.sub.5], while carbon and manganese, present in the melt, reduce phosphoric anhydride. That's why change of the slag basicity in the direction of increase in it of Si[O.sub.2] content causes transition of phosphorus from the slag into the metal, because at high temperature Si[O.sub.2] displaces from 4CaO x [P.sub.2][O.sub.5] phosphorus pentoxide with formation of the silicate (4CaO x [P.sub.2][O.sub.5] + Si[O.sub.2] (r) [P.sub.2][O.sub.5] + + 4CaO x Si[O.sub.2]), and phosphorus of the anhydride is reduced by carbon or iron at slag-metal interface due to which it transits into the metal.