orthophosphoric acid

American

[awr-thoh-fos-fawr-ik, -for-, awr-] / ˈɔr θoʊ fɒsˈfɔr ɪk, -ˈfɒr-, ˌɔr- /

noun

Chemistry.

a colorless, crystalline solid, H 3 PO 4 , the tribasic acid of pentavalent phosphorus: used chiefly in fertilizers, as a source of phosphorus salts, and in soft drinks as an acidulant and flavoring agent.

orthophosphoric acid British

/ ˌɔːθəʊfɒsˈfɒrɪk /

noun

Also called: phosphoric acid. a colourless soluble solid tribasic acid used in the manufacture of fertilizers and soaps. Formula: H 3 PO 4

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of orthophosphoric acid

First recorded in 1870–75; ortho- + phosphoric acid

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

One commercial method of preparing orthophosphoric acid is to treat calcium phosphate rock with concentrated sulfuric acid:

From Textbooks • Feb. 14, 2019

It is possible to prepare pure orthophosphoric acid by dissolving P4O10 in water.

From Textbooks • Feb. 14, 2019

The solid melts at 70.1 °C and decomposes at about 200 °C by disproportionation into phosphine and orthophosphoric acid:

From Textbooks • Feb. 14, 2019

Dropping P4O10 into water produces a hissing sound, heat, and orthophosphoric acid:

From Textbooks • Feb. 14, 2019

On heating orthophosphoric acid to about 225° pyrophosphoric acid is formed in accordance with the following equation: 2H3PO4 = H4P2O7 + H2O.

From An Elementary Study of Chemistry by McPherson, William

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