Samarium(III) oxalate

Samarium(III) oxalate is an inorganic compound, a salt of samarium and oxalic acid with the formula Sm₂(C₂O₄)₃. The compound does not dissolve in water, forms a crystalline hydrate with yellow crystals.

Synthesis

Precipitation of soluble samarium salts with oxalic acid:

$\mathrm{𝟤}𝖲𝗆𝖢{𝗅}_{\mathrm{𝟥}}\mathsf{+}\mathrm{𝟥}{𝖧}_{\mathrm{𝟤}}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}\stackrel{}{\to }𝖲{𝗆}_{\mathrm{𝟤}}\mathsf{(}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}{\mathsf{)}}_{\mathrm{𝟥}}\mathsf{\downarrow }\mathsf{+}\mathrm{𝟨}𝖧𝖢𝗅$

Also a reaction of samarium nitrate and oxalic acid in an aqueous solution:

$\mathrm{𝟤}𝖲𝗆\mathsf{(}𝖭{𝖮}_{\mathrm{𝟥}}{\mathsf{)}}_{\mathrm{𝟥}}\mathsf{+}\mathrm{𝟥}{𝖧}_{\mathrm{𝟤}}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}\stackrel{}{\to }𝖲{𝗆}_{\mathrm{𝟤}}\mathsf{(}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}{\mathsf{)}}_{\mathrm{𝟥}}\mathsf{\downarrow }\mathsf{+}\mathrm{𝟨}𝖧𝖭{𝖮}_{\mathrm{𝟥}}$

Physical properties

Samarium(III) oxalate forms a crystalline hydrate of the composition Sm₂(C₂O₄)₃ • 10H₂O with yellow crystals.

Chemical properties

Decomposes on heating:

$𝖲{𝗆}_{\mathrm{𝟤}}\mathsf{(}{𝖢}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟦}}{\mathsf{)}}_{\mathrm{𝟥}}\stackrel{800^{o}C}{\to }𝖲{𝗆}_{\mathrm{𝟤}}{𝖮}_{\mathrm{𝟥}}\mathsf{+}\mathrm{𝟥}𝖢{𝖮}_{\mathrm{𝟤}}\mathsf{+}\mathrm{𝟥}𝖢𝖮$

Crystalline hydrate Sm₂(C₂O₄)₃ • 10H₂O decomposes stepwise.