Sodium dichromate

  • Sodium bichromate
  • Chromic acid, disodium salt
  • Anhydrous sodium dichromate
Formula
Na2Cr2O7
Structure
Description
A red or red-orange crystalline solid. Odorless.
Uses
Industrial water treatment.

Registry Numbers and Inventories.
CAS
10588-01-9
EC (EINECS/ELINCS)
234-190-3
EC Index Number
024-004-00-7
EC Class
Oxidising; Carcinogenic Category 2; Mutagenic Category 2; Very toxic; Toxic; Harmful; Irritant; Sensitising; Dangerous for the Environment
R 8 21 25 26 37/38 41 43 46 49 50/53
S 45 53 60 61
RTECS
HX7700000
RTECS class
Tumorigen; Mutagen; Reproductive Effector; Human Data
UN (DOT)
3290
Merck
12,8754
Beilstein/Gmelin
21597 (G)
RCRA
D007
EPA OPP
68304
Swiss Giftliste 1
G-2574
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
Cr2Na2O7
Formula mass
261.97
Melting point, °C
356.7
Decomposition point, °C
400
Vapor density (air=1)
10.0
Odor Threshold Odor threshold Odorless
Density
2.35 g/cm3 (20 C)
Solubility in water
650 g/L (25 C)
Heat of fusion
35.70 kJ/mol

Hazards and Protection.
Storage
No unusual storage requirements.Keep tightly closed in a cool place in a tightly closed container.
D2A C D1A
Handling
Containers of this material may be hazardous when emptied. Since emptied containers retain product residues (vapor, liquid, and/or solid), all hazard precautions given in the data sheet must be observed.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
A half facepiece particulate respirator (NIOSH type N95 or better filters) may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, which ever is lowest.. A full-face piece particulate respirator (NIOSH type N100 filters) may be worn up to 50 times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency, or respirator supplier, whichever is lowest. If oil particles (e.g. lubricants, cutting fluids, glycerine, etc.) are present, use a NIOSH type R or P filter. For emergencies or instances where the exposure levels are not known, use a full-facepiece positive-pressure, air-supplied respirator.
Small spills/leaks
Keep material out of water sources and sewers. Build dikes to contain flow as necessary. 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. Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses.
Stability
Stable under ordinary conditions of use and storage.
Incompatibilities
Hydrazine, acetic anhydride, ethanol, trinitrotoluene, hydroxylamine, strong acids, oxidizable materials especially in the presence of strong acid solutions. Any combustible, organic or other readily oxidizable material (paper, wood, sulfur, aluminum or plastics).
Decomposition
urning may produce chrome oxides.

Fire.
Fire fighting
Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.)
Fire potential
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
Hazards
Decomposes to produce oxygen when heated. May ignite other combustibles upon contact.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.
Health
3
 
Flammability
0
 
 
Reactivity
0
 
 
Special
O

Health.
Exposure limit(s)
OSHA PEL: 0.1 mg/m3 ceiling as CrO3
Carcinogin
G-A1, I-1, N-1, CP65
Poison_Class
1*
Exposure effects
Repeated or prolonged exposure can cause ulceration and perforation of the nasal septum, respiratory irritation, liver and kidney damage and ulceration of the skin. Ulcerations at first may be painless, but may penetrate to the bone producing chrome holes. Known to be a human carcinogen.
   Ingestion
Corrosive. Swallowing can cause severe burns of the mouth, throat, and stomach, leading to death. Can cause sore throat, vomiting, diarrhea. May cause violent gastroenteritis, peripheral vascular collapse, dizziness, intense thirst, muscle cramps, shock, coma, abnormal bleeding, fever, liver damage and acute renal failure.
   Inhalation
Corrosive. Extremely destructive to tissues of the mucous membranes and upper respiratory tract. May cause ulceration and perforation of the nasal septum. Symptoms may include sore throat, coughing, shortness of breath, and labored breathing. May produce pulmonary sensitization or allergic asthma. Higher exposures may cause pulmonary edema.
   Skin
Corrosive. Symptoms of redness, pain, and severe burn can occur. Dusts and strong solutions may cause severe irritation. Contact with broken skin may cause ulcers (chrome sores) and absorption, which may cause systemic poisoning, affecting kidney and liver functions. May cause skin sensitization.
   Eyes
Corrosive. Contact can cause blurred vision, redness, pain and severe tissue burns. May cause corneal injury or blindness.

First aid
 
   Ingestion
Have victim drink water or milk; do NOT induce vomiting; call a doctor.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
   Skin
Wash the exposed area with water or 10 to 20 percent ascorbic acid solution for 15 minutes. Consult a physician if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number
3290
Response guide
Hazard class
6.1
Packing Group
I; II
 
USCG CHRIS Code
SCR
 
Std. Transport #
4918499
 
IMO Pollution Category
C
IMO Hazard code
S/P