Potassium chromate

  • Dipotassium chromate
Formula
K2CrO4
Structure
Description
Lemon yellow crystals, odorless.
Uses
Limited application in enamels, finishing leather, rustproofing of metals, being replaced by sodium salt, reagent in analytical chemistry.

Registry Numbers and Inventories.
CAS
7789-00-6
EC (EINECS/ELINCS)
232-140-5
EC Index Number
024-006-00-8
EC Class
Carcinogenic Category 2; Mutagenic Category 2; Irritant; Sensitising; Dangerous for the Environment
R 49 46 36/37/38 43 50/53
S 53 45 60 61
RTECS
GB2940000
RTECS class
Tumorigen; Mutagen; Reproductive Effector
UN (DOT)
9142
Merck
12,7784
Beilstein/Gmelin
12703 (G)
EPA OPP
68301
Swiss Giftliste 1
G-1741
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
CrK2O4
Formula mass
194.20
Melting point, °C
985
Vapor pressure, mmHg
0.001 (940 C)
Vapor density (air=1)
6.7
Saturation Concentration
Approximately zero (1)
Density
2.73 g/cm3
Solubility in water
Soluble
Thermal expansion
0.000105/K (30 C)
Heat of fusion
28.9 kJ/mol

Hazards and Protection.
Storage
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Minimize dust generation and accumulation. 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
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 or absorb material, then place into a suitable clean, dry, closed container for disposal. Avoid generating dusty conditions.
Disposal code
22
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents, hydrazine, sulfur, aluminum, and some plastics.
Decomposition
Oxides of potassium.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Oxidizer. Greatly increases the burning rate of combustible materials. Extinguishing media: Substance is noncombustible; use agent most appropriate to extinguish surrounding fire.
Fire potential
Nonflammable.
Hazards
May increase intensity of fire if in contact with combustible materials. Cool containers and spilled material with plenty of water.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.
Health
3
 
Flammability
0
 
 
Reactivity
1
 
 
Special
O

Health.
Exposure limit(s)
TLV: 0.025 ppm; 0.16 mg/m3 (ACGIH 1991-1992). NIOSH REL: Ca 0.001 mg Cr(VI)/m3 See Appendix A See Appendix C NIOSH IDLH: Potential occupational carcinogen
Carcinogin
G-A1, I-1, N-1, CP65
Poison_Class
1*
Exposure effects
Chronic inhalation and ingestion may cause effects similar to those of acute inhalation and ingestion. Prolonged or repeated exposure may lead to asthma and perforation of the nasal septum. Repeated inhalation may cause chronic bronchitis. May cause liver and kidney damage. May cause cancer in humans.
   Ingestion
May cause severe digestive tract irritation with abdominal pain, nausea, vomiting and diarrhea. Ingestion may cause violent gastroenteritis, circulatory collapse and kidney damage.
   Inhalation
May cause ulceration and perforation of the nasal septum if inhaled in excessive quantities. May cause chemical bronchitis with coughing and difficulty in breathing. Causes severe respiratory tract irritation.
   Skin
May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. May cause deep, penetrating ulcers of the skin. May cause dermatitis.
   Eyes
May cause eye irritation. Exposure to particulates or solution may cause conjunctivitis, ulceration, and corneal abnormalities.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
9142
Response guide
Hazard class
5.1
Packing Group
III
 
USCG CHRIS Code
PCH
 
HS Code
2841 50 00
 
Std. Transport #
4962643