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3D model (JSmol)
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PubChem CID
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| Properties | |
| Fe(NO3)2 | |
| Molar mass | 179.86 g/mol |
| Appearance | Green crystals (hexahydrate) |
| Melting point | 60 °C (140 °F; 333 K)[2] (hexahydrate) |
| Boiling point | 61 °C (142 °F; 334 K)[1] (decomposes) |
| 87.525 g/100 mL | |
| Structure | |
| Orthorhombic[3] | |
| Thermochemistry | |
Std enthalpy of
formation (ΔfH⦵298) |
-497.9 kJ/mol[1] |
| Hazards | |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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428 mg/kg (subcutaneous, rabbit)[4] |
| Related compounds | |
Other anions
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Iron(II) phosphate |
Other cations
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Manganese(II) nitrate Cobalt(II) nitrate |
Related compounds
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Iron(III) nitrate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Iron(II) nitrate is the nitrate salt of iron(II). It is commonly encountered as the green hexahydrate, Fe(NO3)2·6H2O, which is a metal aquo complex, however it is not commercially available unlike iron(III) nitrate due to its instability to air. The salt is soluble in water serves as a ready source of ferrous ions.
No structure of any salt Fe(NO3)2·xH2O has been determined by X-ray crystallography. Nonetheless, the nature of the aquo complex [Fe(H2O)6]2+ is well known and relatively insensitive to the anion. The Fe-O distances are longer for [Fe(H2O)6]2+ (2.13 Å) than for the ferric analogue [Fe(H2O)6]3+ (1.99 Å).[5] Both [Fe(H2O)6]n+ complexes are high spin, which results in pale colors, paramagnetism, and weak Fe-O bonds.

Iron(II) nitrate can be produced in multiple ways, such as the reaction of iron metal with cold dilute nitric acid:
If this reaction is conducted below -10 °C, nonahydrate is produced. It readily releases water to give the hexahydrate.[1]
The above reaction can also co-produce ferric nitrate. Reacting iron(II) sulfate and lead nitrate under dilute ethanol and then evaporating the solution leads to the formation of the green crystals of the hexahydrate. A solution of iron(II) nitrate is produced by the ion-exchange reaction of iron(II) sulfate and barium nitrate, producing a concentration of up to 1.5 M due to the limited solubility of barium nitrate.[1][6][7]
The solution of the iron(II) nitrate-hydrazine complex is produced by the reaction of hydrazine nitrate and ferric nitrate at 40 °C with copper(II) nitrate as a catalyst:[8]
If the compound is used in situ, the compound is produced by the reaction of iron(II) chloride and calcium nitrate:[9][10]
The hexahydrate melts at 60 °C and then decomposes at 61 °C into iron(III) oxide rather than iron(II) oxide.[1] A solution of iron(II) nitrate is much more stable, decomposing at 107 °C to iron(III), with the presence of nitric acid lowering the decomposition temperature. Concentrated nitric acid oxidizes iron(II) nitrate into iron(III) nitrate:[6]
Iron(II) nitrate has no uses, however, there is a potential use for dye removal.[10][9]
| HNO3 | He | ||||||||||||||||
| LiNO3 | Be(NO3)2 | B(NO3)−4 | C | NO−3, NH4NO3 |
O | FNO3 | Ne | ||||||||||
| NaNO3 | Mg(NO3)2 | Al(NO3)3 | Si | P | S | ClONO2 | Ar | ||||||||||
| KNO3 | Ca(NO3)2 | Sc(NO3)3 | Ti(NO3)4 | VO(NO3)3 | Cr(NO3)3 | Mn(NO3)2 | Fe(NO3)3, Fe(NO3)2 |
Co(NO3)2, Co(NO3)3 |
Ni(NO3)2 | Cu(NO3)2 | Zn(NO3)2 | Ga(NO3)3 | Ge | As | Se | Br | Kr |
| RbNO3 | Sr(NO3)2 | Y(NO3)3 | Zr(NO3)4 | Nb | Mo | Tc | Ru | Rh | Pd(NO3)2 | AgNO3 | Cd(NO3)2 | In | Sn | Sb(NO3)3 | Te | I | Xe(NO3)2 |
| CsNO3 | Ba(NO3)2 | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg2(NO3)2, Hg(NO3)2 |
Tl(NO3)3, TlNO3 |
Pb(NO3)2 | Bi(NO3)3 BiO(NO3) |
Po | At | Rn | |
| FrNO3 | Ra(NO3)2 | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og | |
| ↓ | |||||||||||||||||
| La(NO3)3 | Ce(NO3)3, Ce(NO3)4 |
Pr | Nd(NO3)3 | Pm | Sm | Eu(NO3)3 | Gd(NO3)3 | Tb(NO3)3 | Dy | Ho | Er | Tm | Yb | Lu | |||
| Ac(NO3)3 | Th(NO3)4 | Pa | UO2(NO3)2 | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr | |||