Nickel acetate

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  Nickel acetate   
Names: nickel(II) acetate
nickel diacetate
nickelous acetate

Formula: Ni(CH3COO)2 (anhydrous)
Ni(CH3COO)2 · 4H2O (tetrahydrate)
SMILES: CC(=O)[O-].CC(=O)[O-].[Ni+2]
Molar mass: 176.781 g/mol (anhydrous)
248.840 g/mol (tetrahydrate)
Density: 1.798 g/cm3 (anhydrous)
1.744 g/cm3 (tetrahydrate)
Crystal system: monoclinic (tetrahydrate)
a=4.764 Å
4.7640 Å
0.4764 nm
, b=11.771 Å
11.7710 Å
1.1771 nm
, c=8.425 Å
8.4250 Å
0.8425 nm
α=90°
90°  
, β=93.6°
93°35′60.0″  
, γ=90°
90°  

Shapes:
https://media.crystalls.info/w/uploads/media/Oblique_rhombic_prism.json

Color: green
Magnetic properties: paramagnetic
χ=4.69 · 10-3cm³/mol
Stability: stable (tetrahydrate)
Hardness: fragile
Toxicity:
"moderalety toxic" is not in the list (poisonous, highly toxic, moderately toxic, slightly toxic, non-toxic) of allowed values for the "Compound/Toxicity" property.

LD50=350mg/kg

Description

Organic compound, salt of bivalent transitional metal nickel and organic acetic acid. From water solutions crystallizes as tetrahydrate.

Precursors

Reaction between nickel(II) hydroxycarbonate, hydroxide or oxide and acetic acid

Chemical equation:

4CH3COOH + Ni2CO3(OH)2 = 2Ni(CH3COO)2 + 3H2O + CO2
2CH3COOH + Ni(OH)2 = Ni(CH3COO)2 + H2O
2CH3COOH + NiO = Ni(CH3COO)2 + H2O

For preparation of 100.00g of nickel acetate tetrahydrate а 42.48g of hydroxycarbonate or 37.26g of hydroxide or 30.02g of oxide and 68.95g of 70% acetic acid is required.
Add acid to the flask, then add small parts of nickel compound with stirring until it will totally dissolve or, if you use carbonate, until carbon dioxide emission will stop. After reaction will stop, filter the solution and use it for crystal growing.

Reaction between nickel chloride, sulfate or nitrate and excess of concentrated acetic acid

Chemical equation:

2CH3COOH + NiCl2 = Ni(CH3COO)2↓ + 2HCl
2CH3COOH + NiSO4 = Ni(CH3COO)2↓ + H2SO4
2CH3COOH + Ni(NO3)2 = Ni(CH3COO)2↓ + 2HNO3

For preparation of 100.00g of nickel acetate tetrahydrate а 95.52g of nickel chloride hexahydrate or 112.87g of nickel sulfate heptahydrate or 116.86g of nickel nitrate hexahydrate and 48.27g of glacial acid acetic is required.
Add to the flask with hot iron compounds solution a acid 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 glacial acetic acid, then filter the solution and use it for crystal growing.

Yo can simply mix solution without freezing - iron acetate will grow separately from the other salts due to the different crystal lattice..

Reaction between nickel nitrate and sodium acetate

Chemical equation:

2NaCH3COO + Ni(NO3)2 = Ni(CH3COO)2↓ + 2NaNO3

For preparation of 100.00g of nickel acetate tetrahydrate а 116.86g of nickel nitrate hexahydrate and 109.37g of sodium acetate trihydrate is required.
Add to the flask with hot nickel nitrate 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.

Reaction between nickel sulfate and calcium or lead(II) acetate

You can use nickel chloride instead of sulfate if you use lead salt..
Chemical equation:

Ca(CH3COO)2 + NiSO4 = Ni(CH3COO)2 + CaSO4
Pb(CH3COO)2 + NiSO4 = Ni(CH3COO)2 + PbSO4
Pb(CH3COO)2 + NiCl2 = Ni(CH3COO)2 + PbCl2

For preparation of 100.00g of nickel acetate tetrahydrate а 95.52g of nickel chloride hexahydrate or 112.87g of nickel sulfate heptahydrate and 70.80g of calcium acetate monohydrate or 152.44g of lead(II) acetate trihydrate is required.
Add to the flask with calcium or lead acetate solution small parts of nickel salt solution and stir. The large amount of poorly soluble precipitate will form. Settle it out and discard, then filter the solution carefully.

Influence of temperature

Solution hydrolyzes at heating.

Influence of impurities

Addition of ammonium acetate in amount of 3g per 100g of solution increases solubility noticeably, but more large amounts decreases it.

Notes

Crystallizes very slow, even small crystals are growing for few months.

Storage conditions

For crystal storing use hermetic vessel with small amount of saturated solution at the bottom or place wadding moistened with such solution. You can use such alternatives as vessel with vaseline or vegetable oil, organic non-hygroscopic solvent (kerosene, benzine or paraffin). Also you can use acrylate polymer or another kinds of solidifying plastic.

Solubility

Temperatureгр/100,00 гр waterгр/100,00 гр acetic acid
(anhydrous)(tetrahydrate)(anhydrous)
20°C
293.15 K
68 °F
527.67 °R
~12.3
12.3 g/100g
10.953 %
18.2
18.2 g/100g
15.398 %
25°C
298.15 K
77 °F
536.67 °R
16.6
16.6 g/100g
14.237 %
~25.1
25.1 g/100g
20.064 %
30°C
303.15 K
86 °F
545.67 °R
41.6
41.6 g/100g
29.379 %
Soluble in methanol. Insoluble in ethanol, diethyl ether and toluene.

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