Cuprous Oxide or Red Oxide of Cupper (Cu2O)

It occurs in nature as cuprite. It is obtained by heating copper in air above 11000c.

4Cu+o2  above 11000c →   2Cu2o.


If can also be obtained by reducing alkaline Cuso4. (fehling’s solutional with reducing  agents like glucose.


CuSO4+2NaOH      →     Cu(OH)2+Na2SO4

Cu(OH)2       →       CuO+H2O

2CuO + C6H12O6        →     Cu2O + C6H12O7

Glucose                                      gluconic acid




  • It is a red amorphous solid insoluble in water.
  • It dissolves in conc. HCl giving cuprous chloride.

Cu2O + 2Conc.HCl       →         Cu2Cl2 + H2O

  • It dissolves in conc. H2SO4 giving copper sulphate and metallic copper

Cu2O + H2OSO4            →    CuSO4 + H2O + Cu



  • It is used in making ruby-red glass.
  • It is used in making anti-rust paints.
  • It is used in preparation of Cu2Cl2.