"Metal displacement" experiment

How to obtain metallic silver and copper from their salts

This im­pres­sive and fun ex­per­i­ment shows how you can make metal­lic sil­ver and cop­per out of so­lu­tions of their salts at home.

Reagents and equip­ment:

  • cop­per chlo­ride (II) (1 g);
  • sil­ver ni­trate (0.1 g);
  • dis­tilled wa­ter;
  • two test tubes;
  • cop­per and iron wires;
  • a stand.

Step-by-step in­struc­tions

Dis­solve 1 g of cop­per chlo­ride (II) in 35 ml of wa­ter. Then dis­solve 0.1 of sil­ver ni­trate in 35 ml of wa­ter. Pour the so­lu­tions into two test tubes. Place an iron wire in the so­lu­tion of cop­per chlo­ride (II), and a cop­per wire in the so­lu­tion of sil­ver ni­trate. Ob­serve the change in the col­or of the sur­face of the met­als, to or­ange and grey re­spec­tive­ly.

Pro­cess­es de­scrip­tion

All met­als have re­duc­tive prop­er­ties, i.e. the abil­i­ty to give away their elec­trons. The elec­tro­chem­i­cal row of ac­tiv­i­ty of met­als is based on this prop­er­ty, in which the re­duc­tive ac­tiv­i­ty de­creas­es from left to right. Al­ka­line met­als and cal­ci­um re­duce oxy­gen even from wa­ter, but less ac­tive met­als, for ex­am­ple mag­ne­sium, alu­minum, zinc, iron and cad­mi­um, only re­duce oxy­gen from so­lu­tions of acids (apart from ni­tric acid). But if you im­merse them in a so­lu­tion of a salt of a less ac­tive met­al, for ex­am­ple iron in a so­lu­tion of a salt of cop­per, the more ac­tive met­al will re­duce, and the more ac­tive will pass into the so­lu­tion, as we ob­serve in this ex­per­i­ment. It’s im­por­tant to re­mem­ber that this row is only ap­pli­ca­ble to aque­ous so­lu­tions.

Safe­ty pre­cau­tions

You must wear gloves when work­ing with so­lu­tions of salts of cop­per and sil­ver. Do not pour out so­lu­tions of cop­per into the sink or near bod­ies of wa­ter, salts of cop­per are ex­treme­ly poi­sonous for aquat­ic an­i­mals.

Warn­ing! Sub­stances of this ex­per­i­ment are tox­ic and high­ly dan­ger­ous for your health. Do not try this at home. Only un­der pro­fes­sion­al su­per­vi­sion.