a colorless liquid, H2SO3, having a suffocating odor, obtained by dissolving sulfur dioxide in water, known mainly by its salts, which are sulfites: used chiefly in organic synthesis and as a bleach.
Origin of sulfurous acid
First recorded in 1780–90
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A colorless solution of sulfur dioxide in water, characterized by a suffocating sulfurous odor. It is used as a bleaching agent, preservative, and disinfectant. Chemical formula: H2SO3.
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