Sodium dicarbonatocuprate(II)

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   Sodium dicarbonatocuprate(II)   
Names: sodium dicarbonatocuprate(II)
sodium bis(carbonato)cuprate(II)
sodium coppercarbonate(II)
copper(II)-sodium carbonate
Formula: Na2[Cu(CO3)2] (anhydrous)
Na2[Cu(CO3)2] · 3H2O (trihydrate)
SMILES: (C(=O)([O-])[O-].[Cu+2]).[Na+].[Na+]
Molar mass: 229.542 g/mol (anhydrous)
283.587 g/mol (trihydrate)
Density: 2.984 g/cm3 (anhydrous)
2.27 g/cm3 (trihydrate)
Crystal system: monoclinic (anhydrous)
a=6.152 Å, b=8.1237 Å, c=5.6327 Åα=90°, β=115.805°, γ=90°
monoclinic (trihydrate)
a=9.6949 Å, b=6.0949 Å, c=13.7832 Åα=90°, β=91.793°, γ=90°

Color: light-blue
pale blue-green
Magnetic properties: paramagnetic
Hardness: very fragile
Toxicity: slightly toxic


Inorganic complex compound of alkaline metal sodium, transitional metal copper and inorganic carbonic acid. From water solutions crystallizes as trihydrate.


Occurs in nature as chalconatronite and juangodoyite minerals.


Reaction between copper(II) hydroxycarbonate and baking soda or sodium carbonate

Chemical equation:

Cu2(OH)2CO3 + 6NaHCO3 = 2Na2[Cu(CO3)2] + 2NaOH + H2O + CO2
Cu2(OH)2CO3 + 3Na2CO3 = 2Na2[Cu(CO3)2] + 2NaOH

For preparation of 100.00g of sodium dicarbonatocuprate(II) trihydrate а 88.87g of sodium hydrocarbonate or 56.06g of sodium carbonate and 38.99g of copper(II) hydroxycarbonate is required.

Add to flask with hot concentrated solution of sodium hydrocarbonate or carbonate small amount of copper(II) hydroxycarbonate with intense stirring. Heat it to 100°C for few minutes for reaction completion and then filter out. After reaction will stop, filter the solution and use it for crystal growing.


Stable only in solution of baking soda, decomposes in the pure water. Grows mainly as polycrystaline.

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.


Insoluble in water.