Manganese oxalate explained

Manganese oxalate is a chemical compound, a salt of manganese and oxalic acid with the chemical formula .^{[1] [2]} The compound creates light pink crystals, does not dissolve in water, and forms crystalline hydrates.^[3] It occurs naturally as the mineral Lindbergite.^[4]

Synthesis

Exchange reaction between sodium oxalate and manganese chloride:

MnCl _{2} +Na _{2C} _{2O} _{4} +2H _{2O} \xrightarrow{ MnC _{2 O} _{4 ⋅} 2 H _{2O\downarrow} + 2 NaCl }

Physical properties

Manganese oxalate forms light pink crystals.

It does not dissolve in water, p K_sp= 6.8.

Forms crystalline hydrates of the composition MnCO•n HO, where n = 2 and 3.^[5]

Crystalline hydrate of the composition MnCO•2HO forms light pink crystals of the orthorhombic system, space group P2₁2₁2₁, cell parameters a = 0.6262 nm, b = 1.3585 nm, c = 0.6091 nm, Z = 4, melts in its own crystallization water at 100°C.^{[6] [7]}

Chemical properties

Decomposes on heating:

MnC _{2O} _{4} \xrightarrow{215 ^{oC} MnO + CO\uparrow + CO _{2\uparrow} }

Application

• Manganese oxalate is used as an auxiliary siccative.
• Manganese oxalate precursor is used to synthesize single phase nanoparticles of various manganese oxides, such as MnO,, and .^[8]

Notes and References

1. Book: Lunge . Georg . Lunge and Keane's Technical Methods of Chemical Analysis. 2d Ed., Edited by Charles A. Keane ...and P.C.L. Thorne . 1924 . Gurney and Jackson . 61 . 5 August 2021 . en.
2. Book: Young . Philena Anne . The Volumetric Determination of Vanadium and Chromium in Special Alloy Steels: Ceric Sulfate as a Volumetric Oxidizing Agent . 1928 . Mack Printing Company . 74 . 5 August 2021 . en.
3. Donkova . B. . Mehandjiev . D. . Mechanism of decomposition of manganese(II) oxalate dihydrate and manganese(II) oxalate trihydrate . Thermochimica Acta . 2004 . 421 . 1–2 . 141–149 . 10.1016/j.tca.2004.04.001 . 2004TcAc..421..141D . 5 August 2021 . English . 0040-6031.
4. Atencio . Daniel . Coutinho . José M.V. . Graeser . Stefan . Matioli . Paulo A. . Menezes Filho . Luiz A.D. . Lindbergite, a new Mn oxalate dihydrate from Boca Rica mine, Galiléia, Minas Gerais, Brazil, and other occurrences . American Mineralogist . 2004 . 89 . 7 . 1087–1091 . 10.2138/am-2004-0721 . 2004AmMin..89.1087A . 100604132 . 1 December 2021 . English . 1945-3027.
5. Nedyalkova . Miroslava . Antonov . Vladislav . Manganese oxalates - structure-based Insights . Open Chemistry . 1 January 2018 . 16 . 1 . 1176–1183 . 10.1515/chem-2018-0123 . 104343447 . en . 2391-5420. free .
6. Structure disordering and thermal decomposition of manganese oxalate dihydrate, MnC2O4·2H2O . . 1 April 2018 . 260 . 87–94 . 10.1016/j.jssc.2018.01.022 . 5 August 2021 . en . 0022-4596. Puzan . Anna N. . Baumer . Vyacheslav N. . Lisovytskiy . Dmytro V. . Mateychenko . Pavel V. . 2018JSSCh.260...87P .
7. Donkova . Borjana . Avdeev . Georgi . Synthesis and decomposition mechanism of γ-MnC2O4·2H2O rods under non-isothermal and isothermal conditions . . 1 August 2015 . 121 . 2 . 567–577 . 10.1007/s10973-015-4590-4 . 97032400 . 5 August 2021 . en . 1588-2926.
8. Ahmad . Tokeer . Ramanujachary . Kandalam V. . Lofland . Samuel E. . Ganguli . Ashok K. . Nanorods of manganese oxalate: a single source precursor to different manganese oxide nanoparticles (MnO, Mn2O3, Mn3O4) . . 24 November 2004 . 14 . 23 . 3406–3410 . 10.1039/B409010A . 5 August 2021 . en . 1364-5501.