Potassium hexachloroplatinate
3D model (JSmol)
ECHA InfoCard 100.037.239 Edit this at Wikidata
EC Number
  • 240-979-3
RTECS number
  • TP1650000
  • Cl[Pt-2](Cl)(Cl)(Cl)(Cl)Cl.[K+].[K+]
Molar mass 485.99 g/mol
Appearance orange to yellow solid
Density 3.344 g/cm3
Melting point 250 °C (482 °F; 523 K) (decomposes)
0.89 g/100ml (at 25 °C) [1]
GHS labelling:[3]
GHS05: CorrosiveGHS06: ToxicGHS07: Exclamation markGHS08: Health hazard
H301, H317, H318, H334
P261, P264, P270, P272, P280, P285, P301+P310, P302+P352, P304+P341, P305+P351+P338, P310, P321, P330, P333+P313, P342+P311, P363, P405, P501
Flash point 250 °C (482 °F; 523 K)
Safety data sheet (SDS) Oxford MSDS
Related compounds
Other anions
Potassium tetrachloroplatinate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Potassium hexachloroplatinate is the inorganic compound with the formula K2PtCl6. It is a yellow solid that is an example of a comparatively insoluble potassium salt. The salt features the hexachloroplatinate(IV) dianion, which has octahedral coordination geometry.

The precipitation of this compound from solutions of hexachloroplatinic acid was formerly used for the determination of potassium by gravimetric analysis.[4] It is also useful as an intermediate in the recovery of platinum from wastes.[5]


Using salt metathesis reactions, potassium hexachloroplatinate is converted to a variety of quaternary ammonium and related lipophilic salts. These include tetrabutylammonium salt (NBu4)2PtCl6, which has been investigated as a catalyst.[6]

Reduction of potassium hexachloroplatinate with hydrazine dihydrochloride gives the corresponding tetrachloroplatinate salt.[7][8]

Potassium hexachloroplatinate reacts with aqueous ammonia to give chloropentammineplatinum chloride:[9]

K2PtCl6 + 5 NH3 → [PtCl(NH3)5]Cl3 + 2 KCl


Dust containing potassium hexachloroplatinate can be highly allergenic. "Symptoms range from irritation of skin and mucous membranes to life-threatening attacks of asthma."[10]

Related compounds


  1. ^ Grinberg, A. A.; Sibirskaya, V. V. (1967). "Solubility of hexammine and hexahalo platinum(IV) complexes". Zhurnal Neorganicheskoi Khimii. 12: 2069–2071.
  2. ^ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–189. ISBN 978-1-138-56163-2.
  3. ^ "Potassium hexachloroplatinate(IV)". pubchem.ncbi.nlm.nih.gov. Retrieved 27 December 2021.
  4. ^ G. F. Smith; J. L. Gring (1933). "The Separation and Determination of the Alkali Metals Using Perchloric Acid. V. Perchloric Acid and Chloroplatinic Acid in the Determination of Small Amounts of Potassium in the Presence of Large Amounts of Sodium". J. Am. Chem. Soc. 55 (10): 3957–3961. doi:10.1021/ja01337a007.
  5. ^ George B. Kauffman, Larry A. Teter "Recovery of Platinum from Laboratory Residues" Inorganic Syntheses, 1963, volume 7, pp. 232-236. doi:10.1002/9780470132388.ch61
  6. ^ Iovel, I. G.; Goldberg, Y. S.; Shymanska, M. V.; Lukevics, E. (1987). "Quaternary Onium Hexachloroplatinates: Novel Hydrosilylation Catalysts". Organometallics. 6 (7): 1410–1413. doi:10.1021/om00150a007.
  7. ^ George B. Kauffman; Dwaine A. Cowan (1963). "Cis - and trans -Dichlorodiammineplatinum(II)". cis- and trans-Dichlorodiammine Platinum(II). Inorganic Syntheses. Vol. 7. pp. 239–245. doi:10.1002/9780470132388.ch63. ISBN 978-0-470-13238-8.
  8. ^ Keller, R. N.; Moeller, T. (1963). "Potassium Tetrachloroplatinate(II)". Inorg. Synth. 7: 247–250. doi:10.1002/9780470132333.ch79.
  9. ^ Curtis, Neville J.; Lawrance, Geoffrey A.; Sargeson, Alan M. (1986). "Pentaammineplatinum(IV) Complexes". Inorganic Syntheses. 24: 277–279. doi:10.1002/9780470132555.ch74.
  10. ^ Renner, Hermann; Schlamp, Günther; Kleinwächter, Ingo; Drost, Ernst; Lüschow, Hans Martin; Tews, Peter; Panster, Peter; Diehl, Manfred; Lang, Jutta; Kreuzer, Thomas; Knödler, Alfons; Starz, Karl Anton; Dermann, Klaus; Rothaut, Josef; Drieselmann, Ralf; Peter, Catrin; Schiele, Rainer (2001). "Platinum Group Metals and Compounds". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a21_075. ISBN 3-527-30673-0.