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phosphorus pentoxide

[pen-tok-sahyd, -sid] /pɛnˈtɒk saɪd, -sɪd/
noun, Chemistry
1.
a white, deliquescent, crystalline powder, P 2 O 5 , that, depending upon the amount of water it absorbs, forms orthophosphoric acid, metaphosphoric acid, or pyrophosphoric acid, produced by the burning of phosphorus in dry air: used in the preparation of phosphoric acids, as a drying and dehydrating agent, and in organic synthesis.
Also called phosphoric anhydride.
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Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for phosphorus pent oxide

phosphorus pentoxide

noun
1.
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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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