Thiosulfuric acid, disodium salt

  • Chlorine Control
  • Chlorine Cure
  • Declor-It
  • Disodium thiosulfate
  • S-Hydril
  • Sodium hyposulfite
Formula
Na2O3S2
Structure
Description
White, odorless powder.
Uses
To remove chlorine from solution, as antichlor in bleaching of paper pulp, fixer in photography, mordant in dyeing & printing textiles, reducer in chrome dyeing, manufacture leather, extracting of silver from ores, bleaching bone, straw, ivory, reagent in analytical chemistry, antidote (cyanide poisoning).

Registry Numbers and Inventories.
CAS
7772-98-7
EC (EINECS/ELINCS)
231-867-5
RTECS
XN6476000
RTECS class
Other
Merck
12,8844
Beilstein/Gmelin
12718 (G)
EPA OPP
80104
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
Na2O3S2
Formula mass
158.09
Melting point, °C
48
Boiling point, °C
100
Density
1.66 g/cm3
Solubility in water
500 g/L

Hazards and Protection.
Storage
Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from strong acids.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with skin and eyes. Keep container tightly closed. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Sodium nitrite, strong acids, strong oxidizers, water reactive materials. Deliquescent in moist air. Efflorescent in warm dry air.
Decomposition
Oxides of sulfur, hydrogen sulfide, sodium oxide.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Dusts at sufficient concentrations can form explosive mixtures with air. Combustion generates toxic fumes. Extinguishing media: Use water spray, dry chemical, or carbon dioxide.
Health
1
 
Flammability
0
 
 
Reactivity
0
 

Health.
Exposure effects
   Ingestion
Ingestion of large amounts may cause gastrointestinal irritation.
   Inhalation
May cause respiratory tract irritation.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation and possible burns.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid if cough or other symptoms appear.
   Skin
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.