Copper-calcium acetate

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Crystal compoundsSaltsAcetatesCopper-calcium acetate


  Copper-calcium acetate   
Names: copper(II)-calcium acetate
copper-calcium double acetate
copper-calcium tetraacetate
copper-calcium ethanoate
Formula: CuCa(CH3COO)4 (anhydrous)
CuCa(CH3COO)4 · 6H2O (hexahydrate)
SMILES: CC(=O)[O-].CC(=O)[O-].CC(=O)[O-].CC(=O)[O-].[Cu+2][Ca+2]
Molar mass: 339.799 g/mol (anhydrous)
447.889 g/mol (hexahydrate)
Crystal system: tetragonal (hexahydrate)
a=11.152 Å
11.1520 Å
1.1152 nm
, b=11.152 Å
11.1520 Å
1.1152 nm
, c=16.24 Å
16.2400 Å
1.6240 nm
α=90°
90°  
, β=90°
90°  
, γ=90°
90°  

Shapes:
https://media.crystalls.info/w/uploads/media/Octagonal_prism.json
https://media.crystalls.info/w/uploads/media/Truncated_tetragonal_prism.json

Color: bright-blue
Magnetic properties: paramagnetic
Stability: stable (hexahydrate)
Hardness: relatively strong
Toxicity: non-toxic

Description

Organic compound, double salt of bivalent alkaline earth metal calcium, transitional metal copper and organic acetic acid. From water solutions crystallizes as hexahydrate.

Precursors

Mixing hot solutions of copper and calcium acetate

Chemical equation:

Ca(CH3COO)2 + Cu(CH3COO)2 + 6H2O = CuCa(CH3COO)4 · 6H2O

For preparation of 100.00g of copper-calcium acetate hexahydrate а 44.58g of copper acetate monohydrate and 157.34g of calcium acetate monohydrate is required.
Dissolve compounds in hot water apart and then mix solutions into one container with intense stirring. Cooling or evaporation of a solution will cause double salt crystallyzation. After reaction will stop, filter the solution and use it for crystal growing.

You could observe that compounds ratio is not equimolar. The cause is that firstly crystallizes copper acetate which is slight soluble, then begins long period of evaporation of water excess, and only then begins crystallization of double acetate.
If there are 4 or more parts of calcium for 1 part of copper, double salt crystallizes immediately at solution cooling.

Reaction between copper(II) nitrate and calcium acetate

Chemical equation:

2Ca(CH3COO)2 + Cu(NO3)2 = CuCa(CH3COO)4↓ + Ca(NO3)2

For preparation of 100.00g of copper-calcium acetate hexahydrate а 66.01g of copper(II) nitrate hexahydrate and 314.69g of calcium acetate monohydrate is required.
Add to the flask with hot calcium compounds solution a copper compounds solution with heating and stirring. Cooling this mixture will cause forming a large amount of crystalline precipitation. Filter precipitate and wash it wish small amount of cold water, then filter the solution and use it for crystal growing.

Reaction between calcium nitrate and copper(II) acetate

Chemical equation:

2Cu(CH3COO)2 + Ca(NO3)2 = CuCa(CH3COO)4↓ + Cu(NO3)2

For preparation of 100.00g of copper-calcium acetate hexahydrate а 89.15g of copper(II) acetate monohydrate and 210.90g of calcium nitrate tetrahydrate is required.
Add to the flask with hot calcium compounds solution a copper compounds solution with heating and stirring. Cooling this mixture will cause forming a large amount of crystalline precipitation. Filter precipitate and wash it wish small amount of cold water, then filter the solution and use it for crystal growing.

Reaction between calcium nitrate, copper(II) nitrate and sodium acetate

Chemical equation:

4NaCH3COO + Cu(NO3)2 + Ca(NO3)2 = CuCa(CH3COO)4↓ + 4NaNO3

For preparation of 100.00g of copper-calcium acetate hexahydrate а 66.01g of copper(II) nitrate hexahydrate, 210.90g of calcium nitrate tetrahydrate and 121.53g of sodium acetate trihydrate is required.
Add to the flask with hot copper and calcium nitrates solution a sodium acetate solution with heating and stirring. Cooling this mixture will cause forming a large amount of crystalline precipitation. Filter precipitate and wash it wish small amount of cold water, then filter the solution and use it for crystal growing.

Electrolysis of calcium acetate and acetic acid solution with with copper anode

Chemical equation:

Ca(CH3COO)2 + Cu + 2CH3COOH + 6H2O —electrolysis→ CuCa(CH3COO)4 · 6H2O + H2

For preparation of 100.00g of copper-calcium acetate hexahydrate а 14.19g of copper, 157.34g of calcium acetate monohydrate and 38.31g of 70% acetic acid is required.
Add to the flask acetic acid and calcium acetate solution, then place there copper electrodes and plug them to 1.5-5 V power supply. After some time crystal growth will begin at cathode.

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.

Solubility

Soluble in water.

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