Fe(OH)2 + 4 HNO3 → Fe(NO3)3 + NO2 + 3 H2O - Balanced Equation

This is an acid-base reaction (neutralization): Fe(OH)2 is a base, HNO3 is an acid.

This is an oxidation-reduction (redox) reaction:

NV+e-→NIV(reduction)

FeII-1e-→FeIII(oxidation)

HNO3 is an oxidizing agent, Fe(OH)2 is a reducing agent.

Reactants:

• Fe(OH)2 – Iron(II) hydroxide
  • Other names: Ferrous hydroxide
  • Appearance: Green solid
• HNO3 – Nitric acid
  • Other names: Aqua fortis , Spirit of niter , Eau forte ... show moreHydrogen nitrate , Acidum nitricum , Nitric acid (> 70% in water) , Fuming nitric acid , Engravers acid , HONO2 , Red fuming nitric acid , RFNA , White fuming nitric acid (WFNA) show less
  • Appearance: Colorless, yellow or red fuming liquid ; Colourless-to-yellow liquid with pungent odour ; Colorless, yellow, or red, fuming liquid with an acrid, suffocating odor. [Note: Often used in an aqueous solution. Fuming nitric acid is concentrated nitric acid that contains dissolved nitrogen dioxide.]

Products:

• Fe(NO3)3 – Iron(III) nitrate
  • Other names: Ferric nitrate , Nitric acid , Iron(3+) salt , Iron (III) nitrate
  • Appearance: Pale violet crystals | hygroscopic
• NO2 – Nitrogen dioxide
  • Other names: Nitrogen(IV) oxide , Deutoxide of nitrogen , Nitrogen peroxide ... show moreNO2 , NO2(.) , Dinitrogen tetroxide (see notes) , Nitrogen tetroxide , Dinitrogen tetroxide show less
  • Appearance: Brown gas ; Reddish-brown gas or brown or yellow liquid with pungent odour ; Yellowish-brown liquid or reddish-brown gas (above 70°F) with a pungent, acrid odor. [Note: In solid form (below 15°F) it is found structurally as N2O4.]
• H2O – Water, oxidane
  • Other names: Water (H2O) , Hydrogen hydroxide (HH or HOH) , Hydrogen oxide ... show moreDihydrogen monoxide (DHMO) (systematic name) , Hydrogen monoxide , Dihydrogen oxide , Hydric acid , Hydrohydroxic acid , Hydroxic acid , Hydrol , Μ-oxido dihydrogen , Κ1-hydroxyl hydrogen(0) show less
  • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas