Word Study
thiosulphate
CIDE DICTIONARY
thiosulphate, n.
A salt of thiosulphuric acid; -- formerly called hyposulphite . [1913 Webster]
" The sodium salt called in photography by the name sodium hyposulphite, being used as a solvent for the excess of unchanged silver chloride, bromide, and iodide on the sensitive plate." [1913 Webster]
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