Chemical (silicate) garden
How to grow jellyfish from salts
When salts of several metals are added to a solution of silicate glue, multi-colored “seaweed” forms.
Reagents and equipment:
- silicate glue;
- distilled water;
- salts of cobalt, iron, nickel, manganese;
- a small aquarium.
Mix the silicate glue and water in a ratio of 1:1 by mass. Place a small amount of each salt in the solution. Observe how beautiful multicolored "seaweed” gradually grows out of the salt crystals.
Silicates of many metals are insoluble in water. The glue used in the experiment contains relatively soluble potassium and sodium silicates. When salts of 2-3-valence metals are added, an exchange reaction begins, and a film of their insoluble silicates forms around the salt crystals. Water can penetrate this film. Inside the film, the concentration of salt is higher than outside, so a difference of osmotic pressures arises, and the water flows into the silicate shell. This causes the shell to expand and disintegrate, the salt and solution come into contact again, and a new film of silicate is formed. In this way, the “seaweed” grows. The color of the “seaweed” depends on the metal: blue for cobalt, pink for manganese, green for nickel and brown for iron.
Wear protective glasses and gloves. Follow general safety recommendations. Chemical experiments must be carried out in full compliance with the legislation of your country.
Warning! Substances of this experiment are toxic and highly dangerous for your health. Do not try this at home. Only under professional supervision.