Lithium oxalate

Lithium oxalate is an organic compound with the chemical formula Li₂C₂O₄. It is a salt of lithium metal and oxalic acid.^[3][4] It consists of lithium cations Li⁺ and oxalate anions C₂O2−4. Lithium oxalate is soluble in water and converts to lithium oxide when heated.^[5]

Lithium oxalate

Names
IUPAC name Lithium oxalate
Other names Dilithium oxalate di-Lithium oxalate[1] Oxalic acid dilithium salt[2]
Identifiers
CAS Number	553-91-3 Y
3D model (JSmol)	Interactive image
ChemSpider	61669
ECHA InfoCard	100.008.232
EC Number	209-054-1
PubChem CID	68383
UNII	K737OT0E73 N
CompTox Dashboard (EPA)	DTXSID4060288
InChI InChI=1S/C2H2O4-C.2Li/c3-1(4)2(5)6;;/h(H,3,4)(H,5,6);;/q;2*+1/p-2 Key: YNQRWVCLAIUHHI-UHFFFAOYSA-L
SMILES [Li+].[Li+].[O-]C(=O)C([O-])=O
Properties
Chemical formula	Li2C2O4
Molar mass	101.90 g·mol−1
Appearance	Colorless crystalline solid
Density	2.12 g/cm3
Solubility in water	6.6 g per 100 g of water
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H312
Precautionary statements	P264, P270, P280, P301+P312, P302+P352, P312, P322, P330, P363, P501
Related compounds
Related compounds	Sodium oxalate Potassium oxalate Beryllium oxalate Magnesium oxalate Calcium oxalate Strontium oxalate Barium oxalate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis

One of the methods of synthesis is the reaction of direct neutralization of oxalic acid with lithium hydroxide:

2 LiOH + H₂C₂O₄ → Li₂C₂O₄ + 2 H₂O

Properties

The compound crystallizes in the monoclinic system, cell parameters a = 3.400 Å, b = 5.156 Å, c = 9.055 Å, β = 95.60°, Z = 4.^[3]

Lithium oxalate decomposes when heated at 410–500 °C (770–932 °F; 683–773 K):

Li₂C₂O₄ → Li₂CO₃ + CO

Applications

In pyrotechnics, the compound is used to color the flame red.^[6]