“Silver tree” experiment
How to turn a copper tree into a silver one
In this beautiful experiment, we’ll show you how to make needle-like silver crystals using copper.
Safety precautions
Wear protective gloves and glasses. The reactive mixture must not be poured down the sink or into water tanks.
Reagents and equipment:
- copper tree;
- silver nitrate solution 5 g/l;
- beaker.
Step-by-step instructions
Put the copper tree in the beaker. Then pour the silver nitrate solution over it. Observe the silver crystals settle on the surface of the tree.
Processes description
In the reactivity series of metals, copper is to the left of silver, so it can force silver out of solutions of silver salts. Shiny needle-like silver crystals appear on the surface, and the solution turns a blue color, as the copper ions move into the solution. The color is uneven, as the layer of silver is not durable and breaks off, thus “revealing” the copper. The copper reacts increasingly with the silver nitrate solution, and the concentration of copper ions in these areas increases, which means that the coloring of the layer intensifies
Cu + AgNO₃ = Ag + Cu(NO₃)₂
