FeO + 4 HNO3 → Fe(NO3)3 + NO2 + 2 H2O

This is an acid-base reaction (neutralization): FeO is a base, HNO3 is an acid.

This is an oxidation-reduction (redox) reaction:

NV + e- → NIV (reduction)

FeII - 1 e- → FeIII (oxidation)

HNO3 is an oxidizing agent, FeO is a reducing agent.

Reactants:

  • FeO – Iron(II) oxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Ferrous oxide source: wikipedia, accessed: 2019-09-27source: ICSC, accessed: 2019-09-04source: wikidata, accessed: 2019-09-02, Iron monoxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Iron oxide source: wikidata, accessed: 2019-09-02
    • Appearance: Black crystals source: wikipedia, accessed: 2019-09-27; Black solid in various forms source: ICSC, accessed: 2019-09-04
  • HNO3 – Nitric acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Aqua fortis source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02, Spirit of niter source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Eau forte source: wikipedia, accessed: 2019-09-27
    • Appearance: Colorless, yellow or red fuming liquid source: wikipedia, accessed: 2019-09-27; Colourless-to-yellow liquid with pungent odour source: ICSC, accessed: 2019-09-04; 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.] source: NIOSH NPG, accessed: 2019-09-02

Products:

  • Fe(NO3)3 – Iron(III) nitrate source: wikipedia, accessed: 2019-09-27
    • Other names: Ferric nitrate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Nitric acid source: wikipedia, accessed: 2019-09-27, Iron(3+) salt source: wikipedia, accessed: 2019-09-27, Iron (III) nitrate source: wikidata, accessed: 2019-09-02
    • Appearance: Pale violet crystals | hygroscopic source: wikipedia, accessed: 2019-09-27
  • NO2 – Nitrogen dioxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Nitrogen(IV) oxide source: wikipedia, accessed: 2019-09-27, Deutoxide of nitrogen source: wikipedia, accessed: 2019-09-27, Nitrogen peroxide source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
    • Appearance: Brown gas source: wikipedia, accessed: 2019-09-27; Reddish-brown gas or brown or yellow liquid with pungent odour source: ICSC, accessed: 2019-09-04; 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.] source: NIOSH NPG, accessed: 2019-09-02
  • H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27