"Alchemist's gold" experiment

How to turn copper coin gold

In this sim­ple and amaz­ing ex­per­i­ment, we teach you how to make “gold” coat­ings!

Reagents and equip­ment:

  • so­lu­tion of zinc sul­fate (20 g in 50 ml of wa­ter);
  • dis­tilled wa­ter;
  • cop­per coin;
  • zinc;
  • can­dles or dry fuel;
  • burn­er for dry fuel;
  • glass;
  • tweez­ers.

Step-by-step in­struc­tions

Pour the so­lu­tion of zinc sul­fate into the glass. Add zinc gran­ules. Place the cop­per coins in the glass so that they touch the zinc. Heat the glass. Take the “sil­ver” coins out of the glass and heat them over the burn­er. They be­come “gold­en”.

Pro­cess­es de­scrip­tion

When heat­ed, zinc gives up its elec­trons to cop­per. Cop­per be­comes neg­a­tive­ly charged, and at­tracts the zinc ions in the so­lu­tion to its sur­face. Zinc is re­duced on the sur­face of the cop­per, and the coin seems to turn sil­ver. If the coin is heat­ed, it be­comes “gold­en”. This is be­cause on heat­ing, dif­fu­sion from cop­per to zinc takes place, and an al­loy of cop­per and zinc is formed, which has a “gold­en” col­or. If the coin is im­mersed in cold wa­ter, the col­or be­comes rich­er.

Safe­ty pre­cau­tions

Af­ter the ex­per­i­ment, wash your hands thor­ough­ly with soap. Ob­serve safe­ty rules in work­ing with flames and heat­ing de­vices.