phosphoric acid

American  

noun

Chemistry.

1. any of three acids, orthophosphoric acid, H 3 PO 4 , metaphosphoric acid, HPO 3 , or pyrophosphoric acid, H 4 P 2 O 7 , derived from phosphorus pentoxide, P 2 O 5 , and various amounts of water.

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phosphoric acid British  

noun

1. Systematic name: phosphoric(V) acid.  Also called: orthophosphoric acid.  a colourless solid tribasic acid used in the manufacture of fertilizers and soap. Formula: H 3 PO 4

2. any oxyacid of phosphorus produced by reaction between phosphorus pentoxide and water See also metaphosphoric acid pyrophosphoric acid hypophosphoric acid

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phosphoric acid Scientific  

/ fŏs-fôr′ĭk /

1. A clear liquid, or a solid that forms colorless, rhombus-shaped crystals, that is used in fertilizers, detergents, food flavoring, and pharmaceuticals. Chemical formula: H ₃ PO ₄ .

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Etymology

Origin of phosphoric acid

First recorded in 1785–95

Example Sentences

See Examples For:

phosphoric acid

It is then converted into sulfuric acid, which reacts with mined phosphate rock to produce phosphoric acid used to make phosphate fertilizers.

From The Wall Street Journal ● Aug. 28, 2026

Similar bonding patterns have been observed in other phosphoric acid clusters, suggesting that this arrangement may be a common structural feature.

From Science Daily ● Apr. 7, 2026

The tanker, which had been carrying a cargo of phosphoric acid, was identified as the Central Park by the vessel's company.

From Reuters ● Nov. 26, 2023

In 2013, it agreed to pay nearly $199,000 and to reduce air emissions from phosphoric acid production, while denying that it had polluted.

From Seattle Times ● Jul. 14, 2022

Where phosphoric acid is necessary, it can be had in the form of ground bone or acidulated rock, and potash can be had in the form of sulphate or as kainit.

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