Uploaded March 2021 | Updated September 2026, 2 weeks ago
In today’s program: a cool experiment with copper(II) citrate!
Equipment: hot solutions of copper(II) sulfate and sodium citrate, beaker, funnel, filter paper, Petri dish, sheet of metal, matches, paper stencil.
Add a hot solution of sodium citrate to a hot solution of copper(II) sulfate. Observe as a copper(II) citrate precipitate gradually forms. Filter it out and leave it to dry for 24 hours – it will turn into a beautiful turquoise powder. Arrange it in a paper stencil on a sheet of metal and touch it with a burning match. The copper(II) citrate will gradually turn black.
When heated, copper ions are reduced, taking electrons from citrate ions, and turn into very small particles of metallic copper. Unlike a sizable piece of copper, these particles are easily oxidized by atmospheric oxygen, releasing heat and forming black copper(II) oxide. The heat this generates keeps the process going, so even a small amount of heat is enough to cause the decomposition of the entire copper(II) citrate pile.
A similar experiment is included in the “Copper” set from the MEL Chemistry subscription!
Warning! Only under adult supervision.
In today’s program: a cool experiment with copper(II) citrate!
Equipment: hot solutions of copper(II) sulfate and sodium citrate, beaker, funnel, filter paper, Petri dish, sheet of metal, matches, paper stencil.
Add a hot solution of sodium citrate to a hot solution of copper(II) sulfate. Observe as a copper(II) citrate precipitate gradually forms. Filter it out and leave it to dry for 24 hours – it will turn into a beautiful turquoise powder. Arrange it in a paper stencil on a sheet of metal and touch it with a burning match. The copper(II) citrate will gradually turn black.
When heated, copper ions are reduced, taking electrons from citrate ions, and turn into very small particles of metallic copper. Unlike a sizable piece of copper, these particles are easily oxidized by atmospheric oxygen, releasing heat and forming black copper(II) oxide. The heat this generates keeps the process going, so even a small amount of heat is enough to cause the decomposition of the entire copper(II) citrate pile.
A similar experiment is included in the “Copper” set from the MEL Chemistry subscription!
Warning! Only under adult supervision.
