Chemical garden Chemical garden A chemical garden is an experiment in chemistry usually performed by adding metal salts such as copper sulfate or cobalt(II) chloride to an aqueous solution of sodium silicate (otherwise known as waterglass). This results in growth of plant-like forms in minutes to hours. The chemical garden was first observed and described by Johann Rudolf Glauber in 1646. In its original form, the chemical garden involved the introduction of ferrous chloride (FeCl) crystals into a solution of potassium silicate (KSiO). The chemical garden relies on most transition metal silicates being insoluble in water and coloured. A metal salt such
Cobalt with water and oxygen to brown cobalt(III) hydroxide (Co(OH)). At temperatures of 600–700 °C, CoO oxidizes to the blue cobalt(II,III) oxide (CoO), which has a spinel structure. Black cobalt(III) oxide (CoO) is also known. Cobalt oxides are antiferromagnetic at low temperature: CoO (Néel temperature 291 K) and CoO (Néel temperature: 40 K), which is analogous to magnetite (FeO), with a mixture of +2 and +3 oxidation states. The principal chalcogenides of cobalt include the black cobalt(II) sulfides, CoS, which adopts a pyrite-like structure, and cobalt(III) sulfide (CoS). Four dihalides of cobalt(II) are known: cobalt(II) fluoride (CoF, pink), cobalt(II) chloride (CoCl,