Cobalt(II) fluoride Cobalt(II) fluoride Cobalt(II) fluoride is a chemical compound with the formula (CoF). It is a pink crystalline solid compound which is antiferromagnetic at low temperatures (T=37.7 K) The formula is given for both the red tetragonal crystal, (CoF), and the tetrahydrate red orthogonal crystal, (CoF·4HO). CoF is used in oxygen-sensitive fields, namely metal production. In low concentrations, it has public health uses. CoF is sparingly soluble in water. The compound can be dissolved in warm mineral acid, and will decompose in boiling water. Yet the hydrate is water-soluble, especially the di-hydrate CoF·2H O and tri-hydrate CoF·3HO forms of the compound.
Cobalt blue), cobalt(II) bromide (CoBr, green), cobalt(II) iodide (CoI, blue-black). These halides exist in anhydrous and hydrated forms. Whereas the anhydrous dichloride is blue, the hydrate is red. The reduction potential for the reaction + e → is +1.92 V, beyond that for chlorine to chloride, +1.36 V. Consequently, cobalt(III) and chloride would result in the cobalt(III) being reduced to cobalt(II). Because the reduction potential for fluorine to fluoride is so high, +2.87 V, cobalt(III) fluoride is one of the few simple stable cobalt(III) compounds. Cobalt(III) fluoride, which is used in some fluorination reactions, reacts vigorously with water. As for all