This beautiful experiment shows you how to grow your own tree which magically turns copper wire to silver crystals.
- Silver is a less reactive metal than copper, which means copper metal can force silver out of solutions of silver salts
- A single-displacement reaction occurs
- Cu + 2AgNO3 -> 2Ag + Cu(NO3)2
Grow your Silver Tree
- Prepare the silver nitrate solution by dissolving 1g of silver nitrate in 200ml of water. Use distilled water for this process, since tap water would precipitate insoluble silver compounds.
- Use the copper wire to form a tree that fits in the beaker you have chosen.
- Place the copper tree in the beaker. Make sure the sides of the tree aren’t touching the sides of the beaker.
- When ready, pour in the silver nitrate solution so that it touches the tree. The reaction will occur immediately. It will turn blue over time because of the presence of copper 2+ ions.
How does it grow?
In the reactivity series of metals, copper is to the left of silver. This means it can force silver out of solutions of silver salts. In the experiment, silver nitrate and copper wire are used. During the reaction, a single displacement occurs: Copper donates its electrons to form copper 2+ ions, while silver ions are being reduced to form elemental silver.
The colour is uneven, as the layer of silver is not durable and breaks off, thus revealing new copper metal. An increasing amount of copper reacts at the crown of the tree. This means that the concentration of copper ions in these areas increases which means that the colouring of the layer intensifies.
Safety & Disposal
The used solution contains heavy metal salts and has to be disposed of in a labelled container. The disposal requirements may differ in your country.
This experiment deals with dangerous compounds. Silver nitrate is a strong oxidizer, toxic and reacts corrosively with many substances. Wear skin and eye protection at all times.
GHS H&P: H(272, 314, 410) – P(220, 273, 280, 305+351+338, 310, 501)