3 Cu₂S + 6 FeS₂ + 40 HNO₃ → 6 CuSO₄ + 40 NO + 3 Fe₂(SO₄)₃ + 20 H₂O

This is an oxidation-reduction (redox) reaction:

Cu₂S is a reducing agent, FeS₂ is a reducing agent, Cu₂S is a reducing agent, HNO₃ is an oxidizing agent, FeS₂ is a reducing agent.

Reactants:

• Cu₂S – Copper(I) Sulphide
  • Other names: Copper(I) sulfide , Cuprous sulfide , Chalcocite ... show moreCopper glance , Cu2S , Dicopper monosulfide , Dicopper sulphide , Cuprasulfide show less
• FeS₂
  • Names: Ferrous disulfide , Fool's gold , Iron disulfide ... show moreIron persulfide , FeS2 show less
• 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:

• CuSO₄ – Copper(II) sulfate
  • Other names: Cupric sulphate , Blue vitriol (pentahydrate) , Bluestone (pentahydrate) ... show moreBonattite (trihydrate mineral) , Boothite (heptahydrate mineral) , Chalcanthite (pentahydrate mineral) , Chalcocyanite (mineral) , Cupric sulfate , Copper sulfate (anhydrous) , CuSO4 , Copper sulfate , Cupric sulfate anhydrous , Copper monosulphate , Copper sulfate (1:1) , Cupric sulphate anhydrous , Copper sulphate , Copper(2+) sulfate , Copper(II) sulphate , Copper monosulfate , Cupric sulfate, anhydrous , Cupric sulphate, anhydrous , Sulfuric acid, copper(2+) salt(1:1) show less
  • Appearance: Gray-white (anhydrous) | blue (pentahydrate) ; White hygroscopic crystals
• NO – Nitrogen monoxide , Oxidonitrogen(•) (additive)
  • Other names: Nitric oxide , Nitrogen(II) oxide , Nitric oxide (radical) ... show moreMononitrogen monoxide , (.)NO , EDRF , Nitrogen monooxide , [NO] , Oxido de nitrogeno(ii) , NO(.) , Oxido nitrico , Stickstoff(ii)-oxid , NO , Oxyde azotique , Oxyde nitrique , Stickstoffmonoxid , Nitrosyl , (NO)(.) , Monoxido de nitrogeno , Endothelium-derived relaxing factor , Nitroxide radical , Nitroxyl , Nitrosyl radical , Hydroxyamine , Nitrogen oxide , Nitrogen protoxide , Nitrosyl hydride , Nitric Oxide show less
  • Appearance: Colourless gas ; Colourless compressed gas ; Colorless gas. [Note: Shipped as a nonliquefied compressed gas.]
• Fe₂(SO₄)₃ – Iron(III) sulfate
  • Other names: Ferric sulfate , Sulfuric acid , Iron(3+) salt (3:2) ... show moreDiiron tris(sulphate) , Iron tersulfate , Iron sesquisulfate , Iron persulfate , Ferric tersulfate , Ferric sesquisulfate , Ferric persulfate , Diiron trisulfate , Iron(III) sulfate(VI) , Ferric sulfate anhydrous show less
  • Appearance: Grayish-white crystals
• 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