Ammonium hexachloroplatinate

Ammonium hexachloroplatinate

Names
IUPAC name Ammonium hexachloroplatinate(IV)
Other names ammonium chloroplatinate
Identifiers
CAS Number	16919-58-7 Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:59604 Y
ChemSpider	10628022 Y
ECHA InfoCard	100.037.233
InChI InChI=1S/6ClH.2H3N.Pt/h6*1H;2*1H3;/q;;;;;;;;+4/p-4 Y Key: PCCGQTHFYHJATL-UHFFFAOYSA-J Y InChI=1/6ClH.2H3N.Pt/h6*1H;2*1H3;/q;;;;;;;;+4/p-4/rCl6Pt.2H3N/c1-7(2,3,4,5)6;;/h;2*1H3/q-2;;/p+2 Key: PCCGQTHFYHJATL-WPAIPAOFAY
SMILES [NH4+].[NH4+].Cl[Pt-2](Cl)(Cl)(Cl)(Cl)Cl
Properties
Chemical formula	(NH4)2PtCl6
Molar mass	443.87 g/mol
Appearance	yellow crystals
Odor	odorless
Density	3.065 g/cm3
Melting point	380 °C (716 °F; 653 K) decomposes
Solubility in water	0.289 g/100ml (0 °C) 0.7 g/100ml (15 °C) 0.499 g/100ml (20 °C) 3.36 g/100ml (100 °C)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Ammonium hexachloroplatinate, also known as ammonium chloroplatinate, is the inorganic compound with the formula (NH₄)₂[PtCl₆]. It is a rare example of a soluble platinum(IV) salt that is not hygroscopic. It forms intensely yellow solutions in water. In the presence of 1M NH₄Cl, its solubility is only 0.0028 g/100 mL.

The compound consists of separate tetrahedral ammonium cations and octahedral [PtCl₆]²⁻anions. It is usually generated as a fine yellow precipitate by treating a solution of hexachloroplatinic acid with a solution of an ammonium salt. The complex is so poorly soluble that this step is employed in the isolation of platinum from ores and recycled residues.

As analyzed by X-ray crystallography, the salt crystallizes in a cubic motif reminiscent of the fluorite structure. The [PtCl₆]²⁻ centers are octahedral. The NH₄⁺ centers are hydrogen bonded to the chloride ligands.

Ammonium hexachloroplatinate is used in platinum plating. Heating (NH₄)₂[PtCl₆] under a stream of hydrogen at 200 °C produces platinum sponge. Treating this with chlorine gives H₂PtCl₆.