You mostly can’t eat the packs because the beads are a choking hazard, though sometimes manufacturers coat silica gel in toxic cobalt chloride. Either way, the beads are highly absorbent.

Cobalt chloride hexahydrate (CoCl₂·6H₂O) and zinc chloride (ZnCl₂) were mixed in a stoichiometric ratio in deionized water.

This reaction proceeds very slowly at room temperature. The addition of cobalt chloride as a catalyst produces a green cobalt-tartrate intermediate and copious evolution of oxygen and carbon dioxide.

The white solid turns blue in the presence of water. A similar reversible reaction takes place between anhydrous cobalt(II) chloride (which is blue) and water to produce hydrated cobalt(II ...