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.
Chemical element whole number. For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number as it is an average of about 76% chlorine-35 and 24% chlorine-37. Whenever a relative atomic mass value differs by more than 1% from a whole number, it is due to this averaging effect, as significant amounts of more than one isotope are naturally present in a sample of that element. Chemists and nuclear scientists have different definitions of a "pure element". In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the