“Tin dendrite” experiment
How to grow a metal dendrite using electricity
A similar experiment is included in the “Tin” set from the MEL Chemistry subscription
Wear protective gloves and glasses
Reagents and equipment:
- tin(II) chloride (10 g);
- water (30 ml);
- 70% acetic acid (10 ml);
- three Petri dishes;
- two clips without wires;
- two clips with wires;
- electricity source with direct current;
In the beaker, dissolve tin(II) chloride, then add acetic acid. Connect three Petri dishes with the clips, and pour the prepared solution into each dish so that it will make contact with the clips. Connect one end of the clip with wires to the dishes on the side, and the other to the electricity source. Watch the tin dendrite start to grow. If the polarity is changed, the dendrite will start to grow in the opposite direction.
When a direct electric current is passed through a tin(II) chloride solution, electrolysis takes place. On the negative electrode (cathode), tin(II) ions are reduced to metal in the form of crystals resembling fragile tree branches.
Sn²⁺ + 2e⁻ = Sn⁰(metal)