Magnesium oxalate
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IUPAC name
magnesium oxalate
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Systematic IUPAC name
magnesium oxalate
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Other names
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| Identifiers | |
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3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.008.121 |
| EC Number | 208-932-1 |
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PubChem CID
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| UN number | 2811 |
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| Properties | |
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| Molar mass |
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| Appearance | white solid |
| Density | 2.45 g/cm3 |
| Melting point | between 420 and 620 °C (788 and 1,148 °F; 693 and 893 K) 150 °C (302 °F; 423 K) (dihydrate) both decompose |
| Boiling point | Not Applicable |
| 0.038g/100g H2O (anhydrous and dihydrate) | |
| Solubility | insoluble in organics |
| Vapor pressure | 2.51×10−6 mmHg |
| Thermochemistry | |
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Std enthalpy of
formation (ΔfH |
-1269.0 kJ mol−1 |
| Hazards | |
| Main hazards | Irritant |
| NFPA 704 | |
| Flash point | Not Applicable |
| Not Applicable | |
| Related compounds | |
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Related compounds
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Magnesium Oxide |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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| Infobox references | |
Magnesium oxalate is an inorganic compound comprising a magnesium cation with a 2+ charge bonded to an oxalate anion. It has the chemical formula MgC2O4. Magnesium oxalate is a white solid that comes in two forms: an anhydrous form and a dihydrate form where two water molecules are complexed with the structure. Both forms are practically insoluble in water and are insoluble in organic solutions.
Some oxalates can be found in nature and the most known naturally occurring oxalates are whewellite and weddellite, which are calcium oxalates. Magnesium oxalate has been found naturally near Mill of Johnston which is located close to Insch in northeast Scotland. The naturally occurring magnesium oxalate is called glushinskite. The magnesium oxalate was found at the lichen and rock interface on serpentinite. It was found in a creamy white layer which was mixed in with the lichen fungus. A scanning electron micrograph of samples taken showed that the crystals had a pyramidal structure with both curved and striated faces. The size of these crystals ranged from 2 to 5 μm.
Magnesium oxalate can by synthesized by combining a magnesium salt or ion with an oxalate.
A specific example of a synthesis would be mixing Mg(NO3)2 and KOH and then adding that solution to (COOCH3)2. Magnesium oxalate when heated will decompose. First, the dihydrate will decompose at 150 °C into the anhydrous form.
With additional heating the anhydrous form will decompose further into magnesium oxide and carbon oxides between 420 °C and 620 °C. First carbon monoxide and magnesium carbonate form. The carbon monoxide then oxidizes to carbon dioxide and the magnesium carbonate decomposes further to magnesium oxide and carbon dioxide.
Magnesium oxalate dihydrate has also been used in the synthesis of nano sized magnesium oxide. Magnesium oxide is important because it is used as a catalyst, refractory materials, adsorbents, superconductors, and ferroelectric materials. Nano sized particles of magnesium oxide are optimal for some of these uses because of the larger surface area to volume ratio as compared with larger particles. Most common syntheses of magnesium oxide produce fairly large particles, however, the sol-gel synthesis using magnesium oxalate produces highly stable nano sized particles of magnesium oxide. The sol-gel synthesis involves combining a magnesium salt, or in this case magnesium oxalate, with a gelating agent. This process effectively produces nano sized particles of magnesium oxide.
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Wikipedia