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Chemical Datasheet

POTASSIUM CHROMATE

5.1 - Oxidizer 8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7789-00-6
  • 3085
  • Oxidizer
  • Corrosive
  • PCH
NIOSH Pocket Guide International Chem Safety Card
Chromic acid and chromates
  • POTASSIUM CHROMATE
NFPA 704
data unavailable
General Description
Potassium chromate is a yellow crystalline solid. It is soluble in water. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. It is used in chemical analysis, in making pigments for paints and inks, as a fungicide, and to make other chromium compounds.

Hazards

Reactivity Alerts
Air & Water Reactions
Soluble in water.
Fire Hazard
Behavior in Fire: May increase intensity of fire if in contact with combustible materials. Cool containers and spilled material with plenty of water. (USCG, 1999)
Health Hazard
Inhalation causes local irritation of mucous membranes; continuing nose irritation can result in perforation of nasal septum. Ingestion may cause violent gastroenteritis, circulatory collapse, vertigo, coma, and toxic nephritis; ingestion of excessive quantities can be fatal. Contact with eyes causes severe irritation and conjunctivitis. Repeated or prolonged exposure to dust, mist, or solutions may cause dermatitis; contact with breaks in the skin may cause "chrome sores" appearing as slow-healing, hard-rimmed ulcers which leave the area vulnerable to infection. (USCG, 1999)
Reactivity Profile
Oxidizing agents, such as POTASSIUM CHROMATE, can react with reducing agents to generate heat and products that may be gaseous (causing pressurization of closed containers). The products may themselves be capable of further reactions (such as combustion in the air). The chemical reduction of materials in this group can be rapid or even explosive, but often requires initiation (heat, spark, catalyst, addition of a solvent). Explosive mixtures of inorganic oxidizing agents with reducing agents often persist unchanged for long periods if initiation is prevented. Such systems are typically mixtures of solids, but may involve any combination of physical states. Some inorganic oxidizing agents are salts of metals that are soluble in water; dissolution dilutes but does not nullify the oxidizing power of such materials. Organic compounds, in general, have some reducing power and can in principle react with compounds in this class. Actual reactivity varies greatly with the identity of the organic compound. Inorganic oxidizing agents can react violently with active metals, cyanides, esters, and thiocyanates.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from 140 Polymerizable warning [Oxidizers]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. If ammonium nitrate is in a tank, rail car or tank truck and involved in a fire, ISOLATE for 1600 meters (1 mile) in all directions; also, initiate evacuation including emergency responders for 1600 meters (1 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from 140 Polymerizable warning [Oxidizers]:

SMALL FIRE: Use water. Do not use dry chemicals or foams. CO2 or Halon® may provide limited control.

LARGE FIRE: Flood fire area with water from a distance. Do not move cargo or vehicle if cargo has been exposed to heat. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from 140 Polymerizable warning [Oxidizers]:

Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Do not get water inside containers.

SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.

SMALL LIQUID SPILL: Use a non-combustible material like vermiculite or sand to soak up the product and place into a container for later disposal.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. (ERG, 2020)
Protective Clothing
Bu. of Mines approved filter-type respirator; close-fitting safety goggles; rubber boots and apron; safety hat; face shield (USCG, 1999)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP RC TK RF
Potassium chromate (sat) 7789-00-6 Liquid >480 >480 >480 >480⁸ >480⁸ >480⁸
> indicates greater than.
⁸ indicates actual breakthrough time; normalized breakthrough time is not available.

Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...

(DuPont, 2023)

First Aid
INHALATION: move to fresh air.

INGESTION: give large amount of water; induce vomiting; treat peripheral vascular shock vigorously; get medical attention.

EYES: flush with water for at least 15 min.; get medical attention.

SKIN: flush with water; if irritation persists, get medical attention. (USCG, 1999)

Physical Properties

Chemical Formula:
  • K2CrO4
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 2.73 at 64.4°F (USCG, 1999) - Denser than water; will sink
Boiling Point: data unavailable
Molecular Weight: 194.2 (USCG, 1999)
Water Solubility: data unavailable
Ionization Energy/Potential: data unavailable
IDLH: 15 mg Cr(VI)/m3 ; A potential occupational carcinogen. (NIOSH, 2023)

AEGLs (Acute Exposure Guideline Levels)

No AEGL information available.

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Potassium chromate(VI) (7789-00-6) 0.56 mg/m3 9.7 mg/m3 58 mg/m3
(DOE, 2018)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Chromium Compounds N090 & 313
Potassium chromate 7789-00-6 10 pounds 313c

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

No regulatory information available.

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names