Sodium hydrosulfide

  • Sodium sulfhydrate
  • Sodium bisulfide
  • Sodium hydrogen sulfate
  • Sodium mercaptan
  • Sodium sulfhydrate
Formula
NaHS
Structure
Description
Yellow-pink or white crystals, flakes or lumps with a mild, rotten-egg odor.
Uses
Chemical reagent, production of heavy water for nuclear reactors.

Registry Numbers and Inventories.
CAS
16721-80-5
EC (EINECS/ELINCS)
240-778-0
R 31 34
S 25 36/37/38 45 50A
RTECS
WE1900000
RTECS class
Mutagen
UN (DOT)
2318
Merck
12,8730
Beilstein/Gmelin
19160 (G)
RCRA
D003
Swiss Giftliste 1
G-6816
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed

Properties.
Formula
HNaS
Formula mass
56.06
Melting point, °C
43
Decomposition point, °C
350
Vapor pressure, mmHg
49 (20 C)
Odor Threshold Odor threshold 0.0047 ppm
Density
1.79 g/cm3
Solubility in water
620 g/L (20 C)

Hazards and Protection.
Storage
Keep containers tightly closed in a well ventilated area away from food products. Keep away from heat and water. Store at temperatures above 63 degrees F.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Rubber protective equipment, such as apron, boots, splash-proof goggles, gloves; canister-type respirator or self-contained breathing apparatus.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep material out of water sources and sewers. Land spill: Dig a pit, pond, lagoon, holding area to contain liquid or solid material. Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water. Water spill: Add soda ash (Na2CO3). Allow to aerate. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates.
Stability
Readily hydrolyzed in moist air to sodium hydroxide and sodium sulfide.
Incompatibilities
Metals, acids and moisture.
Decomposition
Decomposes to hydrogen sulfide and free alkali. When heated to decomposition it emits toxic fumes of sulfoxides and Na2O.

Fire.
Flash Point,°C
90
Upper exp. limit, %
45.5
Lower exp. limit, %
4.3
Fire fighting
wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. For small fires, use dry chemical, carbon dioxide, or water spray. For large fires, use dry chemical, carbon dioxide, alcohol-resistant foam, or water spray. Cool containers with flooding quantities of water until well after fire is out.
Fire potential
Flammable/combustible material.
Hazards
Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
Combustion products
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
Health
3
 
Flammability
2
 
 
Reactivity
0
 

Health.
Poison_Class
2
Exposure effects
Effects may be delayed.
   Ingestion
May cause severe and permanent damage to the digestive tract. Causes gastrointestinal tract burns. May cause perforation of the digestive tract. May cause systemic effects.
   Inhalation
Causes chemical burns to the respiratory tract. Aspiration may lead to pulmonary edema. Effects of inhalation may be delayed. May cause systemic effects.
   Skin
Causes skin burns. Effects of contact may be delayed. May cause skin rash (in milder cases), and cold and clammy skin with cyanosis or pale color.
   Eyes
Causes eye burns. May cause chemical conjunctivitis and corneal damage.

First aid
 
   Ingestion
If swallowed, do NOT induce vomiting. Get medical aid immediately. If victim is fully conscious, give a cupful of water. Never give anything by mouth to an unconscious person.
   Inhalation
If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
In case of contact, immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid immediately. Wash clothing before reuse.
   Eyes
In case of contact, immediately flush eyes with plenty of water for a t least 15 minutes. Get medical aid immediately.

Transport.
UN number
2318
Response guide
Hazard class
4.2
Packing Group
II
 
USCG CHRIS Code
SHR
 
Std. Transport #
4935267 4935669
 
IMO Chemical Code
17
IMO Pollution Category
B
IMO Hazard code
S/P