Praseodymium(III) oxalate

Praseodymium(III) oxalate is an inorganic compound, a salt of praseodymium metal and oxalic acid, with the chemical formula C6O12Pr2. The compound forms light green crystals that are insoluble in water. It also forms crystalline hydrates.

Preparation
Praseodymium(III) oxalate can be prepared from the reaction of soluble praseodymium salts with oxalic acid:
 * $$\mathsf{2Pr(NO_3)_3 + 3(COOH)_2 \ \xrightarrow{}\ Pr_2(C_2O_4)_3\downarrow + 6HNO_3 }$$

Properties
Praseodymium(III) oxalate forms crystalline hydrates (light green crystals): Pr2(C2O4)3•10H2O. The crystalline hydrate decomposes stepwise when heated:
 * $$\mathsf{Pr_2(C_2O_4)_3\cdot 10H_2O \ \xrightarrow[-H_2O]{T}\ Pr_2(C_2O_4)_3 \ \xrightarrow{T}\ Pr_2O(CO_3)_2 \ \xrightarrow{T}\ Pr_2O_2CO_3 \ \xrightarrow{800^oC}\ Pr_6O_{11} }$$

Uses
Praseodymium(III) oxalate is used as an intermediate product in the synthesis of praseodymium. It is also applied to colour some glasses and enamels. If mixed with certain other materials, the compound paints glass intense yellow.