Hexamminecobalt(III) chloride

From Crystal growing


   Hexamminecobalt(III) chloride   
Names: hexamminecobalt(III) trichloride
cobalt hexammine chloride

Formula: Co(NH3)6Cl3
SMILES: [Cl-].[NH3+][Co-3]([NH3+])([NH3+])([NH3+])([NH3+])[NH3+].[Cl-].[Cl-]
Molar mass: 267.477 g/mol
Density: 1.71 g/cm3
Crystal system: monoclinic
a=12.461 Å, b=21.302 Å, c=12.741 Åα=90°, β=112.968°, γ=90°
Color: yellow
Melting point: 217 °C490.15 K <br />422.6 °F <br />882.27 °R <br />
Stability: stable
Toxicity: poisonous


An unusual example of stable trivalent cobalt. Doesn't form water hydrates.


Reaction between cobalt(II) chloride, ammonia, ammonium chloride and hydrogen peroxide

Chemical equation:

2CoCl2 + 2NH4Cl + 10NH4OH + H2O2 = 2Co(NH3)6Cl3 + 12H2O

For preparation of 100.00g of hexamminecobalt(III) chloride а 88.95g of cobalt(II) chloride hexahydrate, 65.51g of concentrated ammonia, 20.00g of ammonium chloride and 6.36g of hydrogen peroxide is required.
Add to the flask with concentrated ammonia solution hydrogen peroxide and then add small parts of cobalt(II) and ammonium chloride solution with stirring until a precipitation forming will stop. After reaction will stop, filter the solution and use it for crystal growing.

Influence of pH level

Doesn't matter since Co-N bonds are too stable

Storage conditions

Store in its original form or under several layers of varnish at average humidity and room temperature. Do not store in matchboxes or cotton wool and do not heat.


Temperatureгр/100,00 гр water
20°C293.15 K <br />68 °F <br />527.67 °R <br />6.95
50°C323.15 K <br />122 °F <br />581.67 °R <br />12.04
Insoluble in ethanol.