a colorless, crystalline, water-soluble acid of phosphorus, H3PO3, from which phosphites are derived.
Origin of phosphorous acid
First recorded in 1785–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Also called: orthophosphorous acid a white or yellowish hygroscopic crystalline dibasic acid. Formula: H 3 PO 3Systematic name: phosphoric acid
any oxyacid of phosphorus containing less oxygen than the corresponding phosphoric acid
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
A white or yellowish crystalline solid used as a reducing agent. It is hygroscopic (easily absorbs moisture from the atmosphere). Chemical formula: H3PO3.
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