Neptunium(IV) oxalate

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Neptunium(IV) oxalate
  • 20196-48-9 Yes check.svgY
3D model (JSmol)
PubChem CID
  • InChI=1S/2C2H2O4.Np/c2*3-1(4)2(5)6;/h2*(H,3,4)(H,5,6);/p-4
  • C(=O)(C(=O)[O-])[O-].C(=O)(C(=O)[O-])[O-].[Np]
Molar mass 413.04
AppearanceGreen crystals
slightly soluble
GHS Signal word Danger
Related compounds
Related compounds
Thorium dioxalate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Neptunium (IV) oxalate [1] is an inorganic compound, a salt of neptunium and oxalic acid with the chemical formula Np(C2O4)2. [2] The compound is slightly soluble in water, forms crystalline hydrates—green crystals. [3] [4]



Neptunium(IV) oxalate is formed by the oxalic acid precipitation of neptunium (IV) solutions: [5]

Physical properties

Neptunium(IV) oxalate forms a crystalline hydrate of the composition Np(C2O4)2 • 6H2O with green crystals.

It is insoluble in acetone, and slightly soluble in water. [6]

Chemical properties

Neptunium(IV) oxalate decomposes on heating: [7]


Neptunium(IV) oxalate is used as an intermediate product in the purification of neptunium. [8] [9]

Related Research Articles

Neptunium Chemical element, symbol Np and atomic number 93

Neptunium is a chemical element with the symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it being named after Neptune, the next planet beyond Uranus. A neptunium atom has 93 protons and 93 electrons, of which seven are valence electrons. Neptunium metal is silvery and tarnishes when exposed to air. The element occurs in three allotropic forms and it normally exhibits five oxidation states, ranging from +3 to +7. It is radioactive, poisonous, pyrophoric, and capable of accumulating in bones, which makes the handling of neptunium dangerous.

Oxalic acid The simplest dicarboxylic acid

Oxalic acid is an organic acid with the IUPAC name ethanedioic acid and formula HO
. It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name comes from the fact that early investigators isolated oxalic acid from flowering plants of the genus Oxalis, commonly known as wood-sorrels. It occurs naturally in many foods, but excessive ingestion of oxalic acid or prolonged skin contact can be dangerous.

Oxalate Any derivative of oxalic acid; chemical compound containing oxalate moiety

Oxalate (IUPAC: ethanedioate) is a compound found in some foods, which when consumed exits the body through the urine. Excess consumption has been linked to gout and kidney stones. Many metal ions form insoluble precipitates with oxalate, a prominent example being calcium oxalate, the primary constituent of the most common kind of kidney stones. Several plant foods such as the root and/or leaves of spinach, rhubarb, and buckwheat are high in oxalic acid and can contribute to the formation of kidney stones in some individuals. Chemically, oxalate is a dianion with the formula C
, also written (COO)2−
. Either name is often used for derivatives, such as salts of oxalic acid, for example sodium oxalate Na2C2O4, or dimethyl oxalate ((CH3)2C2O4). Oxalate also forms coordination compounds where it is sometimes abbreviated as ox.

Neptunium(IV) oxide Chemical compound

Neptunium(IV) oxide, or neptunium dioxide, is a radioactive, olive green cubic crystalline solid with the formula NpO2. It is a common product of plutonium fission, and emits both α- and γ-particles.

Acetic oxalic anhydride Chemical compound

Acetic oxalic anhydride is an organic compound with a chemical formula of C
and a structural formula of (H3C-(C=O)-O-(C=O)-)2. It can be viewed as a mixed anhydride, formally derived from acetic acid (H3C-(C=O)OH) and oxalic acid ((-(C=O)OH)2), in 2:1 molecular ratio, by the loss of two water molecules.

Neptunium(VI) fluoride Chemical compound

Neptunium(VI) fluoride (NpF6) is the highest fluoride of neptunium, it is also one of seventeen known binary hexafluorides. It is an orange volatile crystalline solid. It is relatively hard to handle, being very corrosive, volatile and radioactive. Neptunium hexafluoride is stable in dry air but reacts vigorously with water.

Thorium oxalate Chemical compound

Thorium oxalate is the inorganic compound with the formula Th(C2O4)2(H2O)4. It is a white insoluble solid prepared by the reaction of thorium(IV) salts with an oxalic acid. The material is a coordination polymer. Each Th(IV) center is bound to 10 oxygen centers: eight provided by the bridging oxalates and two by a pair of aquo ligands. Two additional water of hydration are observed in the lattice.

Sodium hydrogenoxalate Partly deprotonated oxalic acid

Sodium hydrogenoxalate is the sodium salt of hydrogenoxalate. The only difference from oxalic acid is that one of the two hydrogen atoms has been replaced with a sodium atom. Like oxalate, it is toxic for the kidney function if swallowed because of the precipitation of poorly soluble calcium oxalate stones that can obstruct the kidney tubules.

Caesium oxalate (standard IUPAC spelling) dicesium oxalate, or cesium oxalate (American spelling) is the oxalate of caesium. Caesium oxalate has the chemical formula of Cs2C2O4.

Americium(III) hydroxide is a radioactive inorganic compound with the chemical formula Am(OH)3. It consists of one americium atom and three hydroxide groups. It was first discovered in 1944, closely related to the Manhattan Project. However, these results were confidential and were only released to the public in 1945. It was the first isolated sample of americium, and the first americium compound discovered.

Beryllium oxalate Chemical compound

Beryllium oxalate is an inorganic compound, a salt of beryllium metal and oxalic acid with the chemical formula C
. It forms colorless crystals, dissolves in water, and also forms crystalline hydrates. The compound is used to prepare ultra-pure beryllium oxide by thermal decomposition.

Lithium oxalate Chemical compound

Lithium oxalate is an inorganic compound, a salt of lithium metal and oxalic acid with the chemical formula C
. Lithium oxalate is highly insoluble in water and converts to the oxide when heated.

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

Copper oxalate Chemical compound

Copper oxalate is an inorganic compound, a salt of copper metal and oxalic acid with the chemical formula CuC
. The compound is practically insoluble in water, alcohol, ether, and acetic acid but soluble in ammonium hydroxide. Copper oxalate forms a hydrate, which forms acid-blue crystals.

Praseodymium(IV) fluoride Chemical compound

Praseodymium(IV) fluoride (also praseodymium tetrafluoride) is a binary inorganic compound, a highly oxidised metal salt of praseodymium and fluoride with the chemical formula PrF4. The compound forms light yellow crystals.

Yttrium oxalate Chemical compound

Yttrium oxalate is an inorganic compound, a salt of yttrium and oxalic acid with the chemical formula Y2(C2O4)3. The compound does not dissolve in water and forms crystalline hydrates—colorless crystals.

Manganese oxalate is a chemical compound, a salt of manganese and oxalic acid with the chemical formula MnC
. The compound creates light pink crystals, does not dissolve in water, and forms crystalline hydrates.

Tin oxalate Chemical compound

Tin(II) oxalate is an inorganic compound, a salt of tin and oxalic acid with the chemical formula SnC
. The compound looks like colorless crystals, does not dissolve in water, and forms crystalline hydrates.

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.

Neptunium arsenide is a binary inorganic compound of neptunium and arsenic with the chemical formula NpAs. The compound forms crystals.


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