4 KI + 2 CuSO₄ → 2 CuI + I₂ + 2 K₂SO₄

This is an oxidation-reduction (redox) reaction:

CuSO₄ is an oxidizing agent, KI is a reducing agent.

Reactants:

• KI
  • Names: Potassium iodide , KI , Thyrosafe ... show moreThyroshield , Iosat , Kaliumiodid , Nukepills , Potassium Iodide show less
• 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

Products:

• CuI – Copper(I) iodide
  • Other names: Cuprous iodide
  • Appearance: White powder | when impure: tan or brownish
• I₂
  • Names: Iodine , Jod , Iode ... show moreIodio , Yodo , Iodine crystals , Molecular iodine show less
  • Appearance: Bluish black or dark purple crystals with pungent odour ; Violet solid with a sharp, characteristic odor.
• K₂SO₄
  • Names: Potassium sulfate , Potassium sulphate , Dipotassium sulfate ... show moreKaliumsulfat , K2SO4 , Sulfuric acid dipotassium salt show less
  • Appearance: White solid ; Colourless-to-white crystals