Gold(I) chloride

Gold(I) chloride is a compound of gold and chlorine with the chemical formula AuCl.

Gold(I) chloride

Names
IUPAC name Gold(I) chloride
Other names Aurous chloride
Identifiers
CAS Number	10294-29-8 N
3D model (JSmol)	Interactive image
ChEBI	CHEBI:30078 Y
ChemSpider	25464 Y
ECHA InfoCard	100.030.583
PubChem CID	27366
UNII	JD7Y972WU9 N
CompTox Dashboard (EPA)	DTXSID4065026
InChI InChI=1S/Au.ClH/h;1H/q+1;/p-1 Y Key: FDWREHZXQUYJFJ-UHFFFAOYSA-M Y InChI=1/Au.ClH/h;1H/q+1;/p-1 Key: FDWREHZXQUYJFJ-REWHXWOFAM
SMILES [Au]Cl
Properties
Chemical formula	AuCl
Molar mass	232.423 g/mol
Appearance	yellow solid
Density	7.6 g/cm3 [1]
Melting point	170 °C (338 °F; 443 K)
Boiling point	298 °C (568 °F; 571 K) (decomposes)
Solubility in water	very slightly soluble
Solubility	soluble in HCl, HBr organic solvents
Magnetic susceptibility (χ)	−67.0·10−6 cm3/mol
Structure
Crystal structure	Tetragonal, tI16
Space group	I41/amd, No. 141
Hazards
NFPA 704 (fire diamond)	2 0 0
Safety data sheet (SDS)	MSDS
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

Preparation

Gold(I) chloride is prepared by thermal decomposition of gold(III) chloride.

Reactions

Although there is a region of stability at higher temperatures at the appropriate chlorine vapor pressures, the compound is metastable at ambient conditions. When heated with water, the compound dispropotionates to metallic gold and gold(III) chloride in an autoredox reaction:

3 AuCl → 2 Au + AuCl₃

At still higher temperatures, around 500 °C, all gold chlorides convert to gold. This conversion is key to the Miller process, which is widely used for the purification of gold.^[2]

Reaction with potassium bromide yields potassium auric bromide and potassium chloride with separation of metallic gold:

3 AuCl + 4 KBr → KAuBr₄ + 2 Au + 3 KCl

Safety

Gold(I) chloride may irritate the skin and eyes, damage kidney function, and reduce white blood cell counts.