Nomenclature
CAS number: 7772-98-7
Thiosulfuric acid (H
2S
2O
3)
sodium salt (1:2); sodium hyposulfite; “hypo”; antichlor; Sodothiol; Sulfothiorine; Ametox.
Na
2O
3S
2; mol wt 158.11.
Na 29.08%, O 30.36%, S 40.56%.
Na
2S
2O
3.
Description and references
Review of mfg processes: Faith, Keyes & Clark's Industrial Chemicals, F. A.
Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed.,
1975) pp 769-773. Crystal structure of the pentahydrate: A. A. Uraz,
N. Armagan, Acta Crystallogr. B33, 1396 (1977). Toxicity of the pentahydrate: C. Voegtlin et al., J. Pharmacol. Exp. Ther. 25, 297 (1925).
Properties
Powder. Sol in water; practically insol in alcohol.Derivative
Pentahydrate.
Nomenclature
CAS number: 10102-17-7
Na
2O
3S
2.5H
2O; mol wt 248.18.
Na 18.53%, O 51.57%, S 25.84%, H 4.06%.
Properties
Odorless crystals or granules, mp 48° when rapidly heated. Effloresces
in warm dry air; slightly deliquesces in moist air. d 1.69. Loses all its water at 100°;
dec at higher temp. Sol in water; insol in alcohol. Slowly dec in
aq soln at ordinary temp, more rapidly when heated. The aq soln is
practically neutral. pH 6.5-8.0. It dissolves silver halides and
many other salts of silver. Incompat: Iodine, acids;
lead, mercury, and silver salts. LD i.v. in rats: >2.5 g/kg (Voegtlin).Use
To remove chlorine from solns according to the eq:
Na
2S
2O
3 + 4Cl
2 +5H
2O → 2NaHSO
4 + 8HCl and Na
2S
2O
3 + 2HCl → 2NaCl + H
2O + S + SO
2. As “antichlor” in bleaching of paper pulp; as fixer in photography;
for extraction of silver from ores; as mordant in dyeing and printing
textiles; reducer in chrome dyeing; manuf leather; bleaching bone,
straw, ivory; also as titrimetry reagent in analytical chemistry.
Therapeutic Category
Antidote (cyanide).
Therapeutic Category (Veterinary)
Antidote (cyanide). Has been used as
a “general detoxifier”, in bloat, and externally in ringworm, mange.
Keywords
Antidote (Cyanide)