Ammonium dichromate

Ammonium dichromate
Names
	IUPAC name Ammonium dichromate
	Other names Ammonium bichromate; Ammonium pyrochromate
Identifiers
CAS Number	7789-09-5 ;
3D model (JSmol)	Interactive image;
ChemSpider	23002 ;
ECHA InfoCard	100.029.221
PubChem CID	24600;
RTECS number	HX7650000;
UNII	5J18BP595G ;
UN number	1439
CompTox Dashboard (EPA)	DTXSID70872953 ;
	InChI InChI=1S/2Cr.2H3N.7O/h;;21H3;;;;;;;/q;;;;;;;;;2-1/p+2 Key: JOSWYUNQBRPBDN-UHFFFAOYSA-P ; InChI=1/2Cr.2H3N.7O/h;;21H3;;;;;;;/q;;;;;;;;;2-1/p+2/rCr2O7.2H3N/c3-1(4,5)9-2(6,7)8;;/h;2*1H3/q-2;;/p+2 Key: JOSWYUNQBRPBDN-RFRSXZKWAS;
	SMILES [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O.[NH4+].[NH4+];
Properties
Chemical formula	(NH4)2Cr2O7
Molar mass	252.07 g/mol
Appearance	Orange-red crystals
Odor	odorless
Density	2.115 g/cm3
Melting point	180 °C (356 °F; 453 K) decomposes
Solubility in water	18.2 g/100 ml (0 °C); 35.6 g/100 ml (20 °C); 40 g/100 ml (25 °C); 156 g/100 ml (100 °C)
Solubility	insoluble in acetone ; soluble in ethanol
Structure
Crystal structure	monoclinic
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	Very toxic, explosive, oxidizing, carcinogenic, mutagenic, dangerous for the environment
	GHS labelling:
Pictograms
Hazard statements	H272, H301, H312, H314, H317, H330, H334, H340, H350, H360, H372, H410
Precautionary statements	P201, P220, P260, P273, P280, P284
NFPA 704 (fire diamond)	4 2 3 OX
Autoignition; temperature	190 °C (374 °F; 463 K)
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	20–250 mg/kg
Safety data sheet (SDS)	ICSC 1368
Related compounds
Other cations	Potassium dichromate; Sodium dichromate
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Ammonium dichromate is an inorganic compound with the formula (NH₄)₂Cr₂O₇. In this compound, as in all chromates and dichromates, chromium is in a +6 oxidation state, commonly known as hexavalent chromium. It is a salt consisting of ammonium ions and dichromate ions.

Ammonium dichromate is used in demonstrations of tabletop "volcanoes". However, this demonstration has become unpopular in schools due to the compound's carcinogenic nature. It has also been used in pyrotechnics and in the early days of photography.

Names



IUPAC name Ammonium dichromate
Other names Ammonium bichromate Ammonium pyrochromate
Identifiers
CAS Number	7789-09-5^Y
3D model (JSmol)	Interactive image
ChemSpider	23002^Y
ECHA InfoCard	100.029.221
PubChem CID	24600
RTECS number	HX7650000
UNII	5J18BP595G^N
UN number	1439
CompTox Dashboard (EPA)	DTXSID70872953
InChI InChI=1S/2Cr.2H3N.7O/h;;21H3;;;;;;;/q;;;;;;;;;2-1/p+2^Y Key: JOSWYUNQBRPBDN-UHFFFAOYSA-P^Y InChI=1/2Cr.2H3N.7O/h;;21H3;;;;;;;/q;;;;;;;;;2-1/p+2/rCr2O7.2H3N/c3-1(4,5)9-2(6,7)8;;/h;2*1H3/q-2;;/p+2 Key: JOSWYUNQBRPBDN-RFRSXZKWAS
SMILES [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O.[NH4+].[NH4+]
Properties
Chemical formula	(NH₄)₂Cr₂O₇
Molar mass	252.07 g/mol
Appearance	Orange-red crystals
Odor	odorless
Density	2.115 g/cm³
Melting point	180 °C (356 °F; 453 K) decomposes
Solubility in water	18.2 g/100 ml (0 °C) 35.6 g/100 ml (20 °C) 40 g/100 ml (25 °C) 156 g/100 ml (100 °C)
Solubility	insoluble in acetone soluble in ethanol
Structure
Crystal structure	monoclinic
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Very toxic, explosive, oxidizing, carcinogenic, mutagenic, dangerous for the environment
GHS labelling:
Pictograms
Hazard statements	H272, H301, H312, H314, H317, H330, H334, H340, H350, H360, H372, H410
Precautionary statements	P201, P220, P260, P273, P280, P284
NFPA 704 (fire diamond)	4 2 3 OX
Autoignition temperature	190 °C (374 °F; 463 K)
Lethal dose or concentration (LD, LC):
LD₅₀ (median dose)	20–250 mg/kg
Safety data sheet (SDS)	ICSC 1368
Related compounds
Other cations	Potassium dichromate Sodium dichromate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references