phosphorous acid

noun

, Chemistry.

1. a colorless, crystalline, water-soluble acid of phosphorus, H 3 PO 3 , from which phosphites are derived.

phosphorous acid

noun

1. Also calledorthophosphorous acid a white or yellowish hygroscopic crystalline dibasic acid. Formula: H 3 PO 3 Systematic namephosphoric acid
2. any oxyacid of phosphorus containing less oxygen than the corresponding phosphoric acid

phosphorous acid

/ fŏs′fər-əs,fŏs-fôr′əs /

1. A white or yellowish crystalline solid used as a reducing agent. It is hygroscopic (easily absorbs moisture from the atmosphere). Chemical formula: H 3 PO 3 .

Word History and Origins

Origin of phosphorous acid¹

First recorded in 1785–95

Example Sentences

Provided free phosphorus has not been detected, it is necessary to search for phosphorous acid.

From Project Gutenberg

If the materials contain phosphorous acid, a precipitate of phosphide of silver is formed which should be collected and washed.

From Project Gutenberg

It seems probable that the poisonous gas reacts on the oxyhæmoglobin of the blood, and phosphorous acid is formed.

From Project Gutenberg

Hypophosphor′ic, Hypophos′phorous, containing less oxygen than phosphorous acid contains.

From Project Gutenberg

White flaky powder, with an odour of garlic, and rapidly absorbing water to form phosphorous acid.

From Project Gutenberg