Cobalt is a chemical element with the symbol Co. It is a metal that is found in magnetic and superalloys.
It has a high electron affinity and is an important oxidizing agent. It is a component in the formation of many oxides, especially oxalate and chloride.
In aqueous solutions, the pink and blue colors are due to differences in the arrangement of cobalt ions with water molecules. When most of the ions are water, they absorb light and appear pink, while when mostly chloride ions are present, the ions are absorbed by the chlorine molecules and appear blue.
The blue ion [CoCl4]2 forms when hydrochloric acid is added to a solution of hydrated cobalt chloride, which is pink. Other highly basic ligands including carbonate, acetylacetonate, and oxalate induce the formation of Co(III) derivatives.
hydrated cobalt chloride hexahydrate, also called CoCl2*6H2O, is the most common cobalt salt in the laboratory. It has six water molecules bonded to each of its formula units, with the hexa-structure attracting cobalt chloride slat molecules.
When heated, the hexahydrate converts to anhydrous cobalt chloride. The molar mass of this form is higher than the hexahydrate, so it does not dissolve in water as readily.
This reagent grade cobalt chloride is ideal for educational and research laboratories. It comes in a 100 gram or 500 gram bottle and has safety instructions printed directly on the label. Each bottle has a resealable lid. It is manufactured by American Elements under ASTM standards.