AMMONIUM CHROMATE Property

Melting point:

180°C (dec.)

Density 

1.91 g/mL at 25 °C (lit.)

solubility 

H₂O: 1 M at 20 °C, clear, yellow

form 

Crystalline

Specific Gravity

1.91

color 

Yellow-orange

Water Solubility 

Soluble in water. Slightly soluble in liquid ammonia, acetone, methanol. Insoluble in ethanol.

Merck 

14,510

Exposure limits

ACGIH: TWA 0.0002 mg/m3; STEL 0.0005 mg/m3 (Skin)
OSHA: Ceiling 0.1 mg/m3
NIOSH: IDLH 15 mg/m3; TWA 0.0002 mg/m3

CAS DataBase Reference

7788-98-9(CAS DataBase Reference)

EPA Substance Registry System

Ammonium chromate (7788-98-9)

Safety

Hazard Codes 

O,T,N

Risk Statements 

49-8-43-50/53-34

Safety Statements 

53-17-45-60-61-36/37/39-26

RIDADR 

UN 1479 5.1/PG 2

WGK Germany 

3

RTECS 

GB2880000

TSCA 

Yes

HazardClass 

5.1

PackingGroup 

III

Hazardous Substances Data

7788-98-9(Hazardous Substances Data)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H272May intensify fire; oxidizer

H314Causes severe skin burns and eye damage

H334May cause allergy or asthma symptoms or breathing difficulties if inhaled

H350May cause cancer

H410Very toxic to aquatic life with long lasting effects

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

AMMONIUM CHROMATE Chemical Properties,Usage,Production

Chemical Properties

Ammonium chromate is a yellow crystalline compound which can be used in solution, which is yellow with an ammonia odor.

Uses

Ammonium chromate, is used in photography as a sensitizer for gelatin coatings. It's often used in photography, textile printing, and fixing chromate dyes on wool. It is also used as an analytical reagent, catalyst.

Uses

Reagent for the preparation of a solid heterogeneous oxidizing agent for liquid phase oxidation of alcohols.

Uses

Sensitizing gelatin in photography, in textile printing pastes, in fixing chromate dyes on wool, and as a reagent in analytical chemistry.

Hazard

Toxic by inhalation, strong irritant. Con- firmed carcinogen.

Safety Profile

A poison. Mutation data reported. See also CHROMIUM COMPOUNDS. A powerful oxidizer. An explosion hazard when shocked or heated. When heated to decomposition it emits toxic fumes of NH3, Cr03, and NOx. Incompatible with reducing agents.

Potential Exposure

It is used to inhibit corrosion and in dyeing, photography and many chemical reactions. Used as a fungicide and fire retardant.

Shipping

UN3288 Toxic solids, inorganic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required.

Purification Methods

Crystallise it from weak aqueous ammonia (ca 2.5mL/g) by cooling from room temperature. It loses NH3 on heating to form ammonium dichromate. POISONOUS.

Incompatibilities

A strong oxidizer and an explosive. Contact with combustible, organic and other readily oxidizable substances may cause fire and explosions. Hydrazine, other reducing agents. Corrosive to metals.

Waste Disposal

Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal. Addition of a large volume of a reducing agent solution (hypo, bisulfite or ferrous salt, and acidify with 3 M sulfuric acid). When reduction is complete, flush to drain with large volumes of water.