Sodium dioxalatocuprate (II)

Sodium dioxalatocuprate(II)
Names:	sodium dioxalatocuprate(II) sodium bis(oxalato)cuprate(II) sodium copperoxalate copper(II) sodium oxalate
Formula:	Na2[Cu(C2O4)2] (anhydrous) Na2[Cu(C2O4)2] · 2H2O (dihydrate)
Molar mass:	285.562 g/mol (anhydrous) 321.592 g/mol (dihydrate)
Density:	2.24 g/cm3 (dihydrate)
Crystal system:	triclinic (dihydrate) a=7.536 Å, b=9.473 Å, c=3.576 Åα=81.90°, β=103.77°, γ=108.09°
Shapes:	https://en.crystalls.info/w/uploads/media/5/52/Needle.json Needle
Color:	blue light blue
Decomposition point:	255 °C528.15 K <br />491 °F <br />950.67 °R <br /> (dihydrate)
Stability:	stable (dihydrate)
Hardness:	very fragile

Description

Organic coordination complex, salt of alkaline metal sodium, transitional metal copper and organic oxalic acid. From water solutions crystallizes as dihydrate.

Minerals

Occurs in nature as wheatleyite mineral.

Precursors

Reaction between copper(II) sulfate and sodium oxalate

Chemical equation:

CuSO₄ + 4Na₂C₂O₄ = Na₂[Cu(C₂O₄)₂] + Na₂SO₄

For preparation of 100.00g of sodium dioxalatocuprate(II) dihydrate

dihydrate

anhydrous

а 49.63g of copper(II) sulfate and 166.67g of sodium oxalate is required.

Add to the flask with hot copper(II) sulfate solution a sodium oxalate solution with heating and stirring. Cooling this mixture will cause forming a large amount of crystalline precipitate.

Reaction between copper(II) oxalate and sodium oxalate

Chemical equation:

CuC₂O₄ + Na₂C₂O₄ = Na₂[Cu(C₂O₄)₂]

For preparation of 100.00g of sodium dioxalatocuprate(II) dihydrate

dihydrate

anhydrous

а 47.13g of copper(II) oxalate and 41.67g of sodium oxalate is required.

Add to the flask with copper oxalate a sodium oxalate solution with stirring.

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

Slightly soluble in water.

Gallery

• 

  Sodium dioxalatocuprate(II)Zts16, Sciencemadness forumZts16Sciencemadness forum

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  Sodium dioxalatocuprate(II)Zts16, Sciencemadness forumZts16Sciencemadness forum

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  Needles and clustersSodium dioxalatocuprate(II), TwitterVicky SilvianaTwitter

Sources

• A. Gleizes, F. Maury, and J. Galy Crystal structure and magnetism of sodium bis(oxalato)cuprate(II) dihydrate
• A. Gleizes, F. Maury, and J. Galy Crystal structure and magnetism of sodium bis(oxalato)cuprate(II) dihydrate
• P. Chananont, P. Nixon, J. Waters and T. Waters The structure of disodium catena-bis(mu-oxalato)-cuprate(II) dihydrate
• P. Chananont, P. Nixon, J. Waters and T. Waters The structure of disodium catena-bis(mu-oxalato)-cuprate(II) dihydrate
• R. Frost, A. Locke, W. Martens Thermogravimetric analysis of wheatleyite Na2Cu2+(C2O4)2·2H2O
• R. Rouse, D. Peacor, P. Dunn, W. Simmons, and D. Newbury Wheatleyite, Na2Cu(C2O4)2·2H2O, a natural sodium copper salt of oxalic acid
• Mineralogy Database site
• American Mineralogist Crystal Structure Database

Navigation

Copper compounds
Salts	Copper (Cu) • Copper(II) acetate (Cu(CH3COO)2) • Copper(II) dihydrophosphate (Cu(H2PO4)2) • Copper(II) formate (Cu(COOH)2) • Copper(II) lactate (Cu(C3H5O3)2) • Copper(II) nitrate (Cu(NO3)2) • Copper(II) sulfamate (Cu(NH2SO3)2) • Copper(II) sulfate (CuSO4) • Copper(II) tartrate (CuC4H4O6) • Copper(II) chloride (CuCl2)
Double salts	Copper-calcium acetate (CuCa(CH3COO)4) • Copper(II)-iron(II) sulfate ((Cu,Fe)SO4) • Copper(II)-ammonium sulfate ((NH4)2Cu(SO4)2) • Copper(II)-potassium sulfate (K2Cu(SO4)2)
Complexes	Dicarbonatocuprates • Dioxalatocuprates • Bis-thetramethylethylenediaminecopper(II) nitrate ([Cu((H3CNCH3)2C4H8)](NO3)2) • Glycinecopper(II) sulfate ([Cu(NH2CH2COOH)]SO4) • Copper(II) formate and urea complex (Cu(HCOO)2 · 2CO(NH2)2) • Potassium dioxalatocuprate(II) (K2[Cu(C2O4)2]) • Sodium dioxalatocuprate(II) (Na2[Cu(C2O4)2]) • Sodium dicarbonatocuprate(II) (Na2[Cu(CO3)2]) • Tetraamminecopper(II) sulfate ([Cu(NH3)4]SO4) • Tetrachlorocuprates • Tris(hydroxymethyl)methanoaminecopper(II) sulfate ([Cu(NH2C(CH2OH)3)4]SO4)

Oxalates
Salts	Ammonium oxalate ((NH4)2C2O4) • Cobalt(II) oxalate (CoC2O4) • Diglycine oxalate ((NH2CH2COOH)3 · H2C2O4) • Neodymium oxalate (Nd2(C2O4)3) • Oxalic acid (HOOCСООН) • Sodium oxalate (Na2C2O4) • Tris(ethylenediamine)nickel oxalate ([Ni(H2NCH2CH2NH2)3]C2O4)
Dioxalatocuprates	Ammonium dioxalatocuprate(II) ((NH4)2[Cu(C2O4)2]) • Potassium dioxalatocuprate(II) (K2[Cu(C2O4)2]) • Sodium dioxalatocuprate(II) (Na2[Cu(C2O4)2])
Trioxalatoaluminates	Potassium trioxalatoaluminate (K3[Al(C2O4)3]) • Sodium trioxalatoaluminate (Na3[Al(C2O4)3])
Trioxalatochromates	Potassium trioxalatochromate(III) (K3[Cr(C2O4)3]) • Sodium trioxalatochromate(III) (Ns3[Cr(C2O4)3])
Trioxalatocobaltates	Potassium trioxalatocobaltate(III) (K3[Co(C2O4)3])
Trioxalatoferrates	Ammonium trioxalatoferrate(III) ((NH4)3[Fe(C2O4)3]) • Lithium trioxalatoferrate(III) (Li3[Fe(C2O4)3]) • Lithium trioxalatoferrate(III)-chloride (Li4[Fe(C2O4)3]Cl) Potassium trioxalatoferrate(III) (K3[Fe(C2O4)3]) • Dipotassium-sodium trioxalatoferrate(III) (K2Na[Fe(C2O4)3]) • Potassium-sodium trioxalatoferrate(III) (K5Na[Fe(C2O4)3]2) • Sodium trioxalatoferrate(III) (Na3[Fe(C2O4)3])
Ethers	Dimethyloxalate ((CH3)2C2O4)