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

The white fumes of phosphorous acid floated out into the air, and began to diffuse themselves through the hall towards the ventilation outlets at the sides and rear.

From Project Gutenberg

I distilled two parts of finely pulverised manganese with one part of the phosphorous acid of urine in the same way as is indicated in the preceding paragraph, I likewise obtained fire-air.

From Project Gutenberg

The important acids of phosphorus are the following: H3PO3 phosphorous acid.

From Project Gutenberg

Bodies absorbing oxygen, as sulphurous acid, phosphorous acid, and alcohols, decolorize it; under the influence of oxygen its color is restored.

From Project Gutenberg