20 HCl + 4 K₂CrO₄ + 3 P₂O₃ → H₂O + 8 KCl + 6 H₃PO₄ + 4 CrCl₃

This is an acid-base reaction (neutralization): HCl is an acid, K₂CrO₄ is a base.

This is an oxidation-reduction (redox) reaction:

P₂O₃ is a reducing agent, K₂CrO₄ is an oxidizing agent.

Reactants:

• HCl – Chlorane , Hydrogen chloride
  • Other names: Hydrochloric acid , M , Uriatic acid ... show moreHydronium chloride , Chlorhydric Acid , Hydrochloric acid gas , HCl , Anhydrous hydrogen chloride , Hydrochloric acid, anhydrous , Aqueous hydrogen chloride , [Note: Often used in an aqueous solution.] show less
  • Appearance: Colorless, transparent liquid, fumes in air if concentrated ; Colorless gas ; Colourless compressed liquefied gas with pungent odour ; Colorless to slightly yellow gas with a pungent, irritating odor. [Note: Shipped as a liquefied compressed gas.]
• K₂CrO₄ – Potassium chromate
  • Other names: Chromic acid , (K2CrO4) , Dipotassium salt ... show moreDipotassium chromate , Potassium chromate(VI) , Bipotassium chromate , Chromic acid, dipotassium salt , Dipotassium monochromate show less
  • Appearance: Yellow powder ; Yellow crystals
• P₂O₃
  • Names: Phosphorus trioxide , Phosphorus(III) oxide , Phosphorus sesquioxide ... show morePhosphorous oxide , Phosphorous anhydride , Tetraphosphorous hexoxide show less
  • Appearance: Colourless monoclinic crystals or liquid

Products:

• 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
• KCl
  • Names: Potassium chloride , Sylvite , Muriate of potash ... show moreKlor-Con M15 , K-Lease , Klor-Con 8 , K+10 , K+8 , Klor-Con M10 , Micro-K 10 , Kato , Kaon Cl-10 , Kaon-Cl , Kaon Cl , Micro-K , Klor-Con 10Meq , Klor-Con 10 , Micro-K Ls , K-dur , Klor-Con , Klor-Con M20 , Slow-K , Ten-K , Klotrix , [KCl] , Kaliumchlorid , Chloride of potash , Kaon-CL 10 , Klor-CON , KCl , Monopotassium chloride , K-Tab , Chlorid draselny , Potassium Chloride show less
  • Appearance: White crystalline solid ; Colourless hygroscopic crystals
• H₃PO₄
  • Names: Phosphoric acid , Orthophosphoric acid , Phosphoric(V) acid ... show moreWhite phosphoric acid , [PO(OH)3] , H3PO4 , E338 , Phosphoric acid (aqueous) show less
  • Appearance: Hygroscopic colourless crystals ; Thick, colorless, odorless, crystalline solid. [Note: Often used in an aqueous solution.]
• CrCl₃ – Chromium(III) chloride , Chromium trichloride
  • Other names: Chromic chloride , Chromium(iii) chloride (anhydrous) , Chromium(3+) trichloride ... show moreCrCl3 , Anhydrous chromium(III) chloride , Chromium chloride , Puratronic chromium chloride , Trichlorochromium , Chromic chloride anhydrous show less
  • Appearance: Purple (anhydrous), dark green (hexahydrate) ; Violet crystals