Hydrogen selenide

  • Hydroselenic acid
  • Selenium hydride
  • Dihydrogen selenide
Formula
H2Se
Structure
Description
Hydrogen selenide is a colorless gas with an offensive odor.
Uses
Preparation of metallic selenides and organoselenium compounds, in doping as mix for preparation of semiconductor materials containing controlled amounts of significant impurities.

Registry Numbers and Inventories.
CAS
7783-07-5
EC (EINECS/ELINCS)
231-978-9
RTECS
MX1050000
RTECS class
Other
UN (DOT)
2202
Merck
12,4842
Beilstein/Gmelin
611 (G)
RCRA
D010
Swiss Giftliste 1
G-2848
Canada DSL/NDSL
DSL
US TSCA
Listed
Korea ECL
Listed

Properties.
Formula
H2Se
Formula mass
80.98
Melting point, °C
-66
Boiling point, °C
-41
Vapor pressure, mmHg
6611 (25 C)
Vapor density (air=1)
2.12
Odor Threshold Odor threshold 0.3 ppm
Critical pressure
91
Density
2.12 g/cm3 (-42 C)
Solubility in water
9 g/L (15 C)
Viscosity
21.9 erg/cm2 (4 C)
Dipole moment
0.4 D
Dielectric constant
1.473 (17 C)
Thermal expansion
0.003683/K (0 C)
Heat of fusion
2.5 kJ/mol
Heat of vaporization
19.5 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
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
Wear appropriate protective gloves, clothing and goggles. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors.
Stability
Hydrogen selenide. Decomposes rapidly in air to form elemental selenium and water.
Incompatibilities
It forms explosive mixtures with air React vigorously with strong oxidizing reagents, e.g., hydrogen peroxide, nitric acid.
Decomposition
Decomposes on heating above 100 C producing toxic and flammable products including selenium and hydrogen.

Fire.
Fire fighting
Isolate for 1/2 mile in all directions if tank car or truck is involved in fire. Stay upwind; keep out of low areas. Withdraw immediately in case of rising sound from venting safety device or any discoloration of tank due to fire. Wear self-contained breathing apparatus and full protective clothing. Cool containers that are exposed to flames with water until well after the fire is out.Let tank car, tank truck, or storage tank burn unless leak can be stopped. Small fires: dry chemical or carbon dioxide. Large fires: water spray, fog, or foam.
Fire potential
Fire potential:highly flammable.
Hazards
It is extremely flammable; may be ignited by heat, sparks, or flames. Vapors may travel to a source of ignition and flash back. Container may explode in heat of fire. It is dangerous and forms explosive mixtures with air. It can decompose into toxic fumes. Incompatible with acid, water, halogenated hydrocarbons, oxidizers, hydrogen peroxide, and nitric acid. It should be stored out of the direct rays of the sun. Keep away from heat and flames.
Combustion products
Fire will produce irritating, corrosive and/or toxic gases.
Health
3
 
Flammability
3
 

Health.
Exposure limit(s)
TLV (as Se): 0.05 ppm; 0.16 mg/m3 (as TWA) (ACGIH 1992-1993). OSHA PEL: TWA 0.05 ppm (0.2 mg/m3) NIOSH REL: TWA 0.05 ppm (0.2 mg/m3) NIOSH IDLH: 1 ppm
Poison_Class
1
Exposure effects
Some spontaneous abortions and neonates born with bilateral talipes equinovarus (club foot deformity) have been noted in selenite-exposed female workers, suggesting that occupational exposure to selenium compounds may pose a human reproductive risk. <br>Studies with potassium selenate and sodium selenite in rats, rabbits, mice, and hamsters have failed to produce teratogenic effects; an unspecified selenium salt caused teratogenic effects in sheep. <br>Irregular menses have been reported in Japanese selenium rectifier workers. <br>Selenium may be transferred to the fetus through the placenta. <br>Selenium appears in the breast milk, with the levels depending on dietary intake. <br>No information about possible male reproductive effects was found in available references.
   Ingestion
Hydrogen selenide can cause nausea and vomiting.
   Inhalation
Initial odor may be irritating or foul and may deaden your sense of smell. May be fatal.
   Skin
Hydrogen selenide is irritating to skin.
   Eyes
May cause burns.

First aid
 
   Ingestion
The possible benefit of early removal of some ingested material by cautious gastric lavage must be weighed against potential complications of bleeding or perforation. Activated charcoal activated charcoal binds most toxic agents and can decrease their systemic absorption if administered soon after ingestion. Activated charcoal: administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists. Treat dermal irritation or burns with standard topical therapy. Patients developing dermal hypersensitivity reactions may require treatment with systemic or topical corticosteroids or antihistamines.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
2202
Response guide
Hazard class
2.3
PRTC
T
USCG CHRIS Code
HSE
 
Std. Transport #
4920122