Sodium thiosulfate pentahydrate

  • Hypo
  • Disodium thiosulphate pentahydrate
  • Thiosulfuric acid, disodium salt, pentahydrate
Formula
Na2S2O3 . 5H2O
Structure
Description
colorless crystals

Registry Numbers and Inventories.
CAS
10102-17-7
EC (EINECS/ELINCS)
231-867-5
R 36/38
RTECS
WE6660000
RTECS class
Drug; Human Data
Merck
12,8844
Beilstein/Gmelin
56152 (G)
Swiss Giftliste 1
G-2622
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
Na2O3S2 . 5 H2O
Formula mass
248.21
Melting point, °C
48
Density
1.67 g/cm3
Solubility in water
701 g/L (20 C)
Heat of fusion
51.8 kJ/mol

Hazards and Protection.
Storage
Store in a tightly closed container. Keep from contact with oxidizing materials. Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from strong acids. Store protected from moisture.
Handling
Wash thoroughly after handling. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid prolonged or repeated contact with skin. Avoid contact with eyes, skin, and clothing. 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 prevent skin exposure.
Respirators
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Provide ventilation.
Disposal code
28
Stability
Stable under normal shipping and handling conditions.
Incompatibilities
Moisture, strong acids, strong bases, strong oxidizing agents.
Decomposition
Irritating and toxic fumes and gases, 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. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Wear appropriate protective clothing to prevent contact with skin and eyes. Wear a self-contained breathing apparatus (SCBA) to prevent contact with thermal decomposition products. Extinguishing media: Use agent most appropriate to extinguish fire. In case of fire use water spray, dry chemical, carbon dioxide, or appropriate foam.
Health
1
 
Flammability
0
 
 
Reactivity
0
 

Health.
Poison_Class
4
Exposure effects
   Ingestion
Ingestion of large amounts may cause gastrointestinal irritation. The toxicological properties of this substance have not been fully investigated.
   Inhalation
May cause respiratory tract irritation. Low hazard for usual industrial handling. The toxicological properties of this substance have not been fully investigated.
   Skin
Prolonged and/or repeated contact may cause irritation and/or dermatitis.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   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. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
HS Code
2832 30 00