Cobalt it reacts slowly with mineral acids, and very slowly with moist, but not with dry, air. Common oxidation states of cobalt include +2 and +3, although compounds with oxidation states ranging from −3 to +5 are also known. A common oxidation state for simple compounds is +2 (cobalt(II)). These salts form the pink-colored metal aquo complex [Co(HO)] in water. Addition of chloride gives the intensely blue . In a borax bead flame test, cobalt shows deep blue in both oxidizing and reducing flames. Several oxides of cobalt are known. Green cobalt(II) oxide (CoO) has rocksalt structure. It is readily oxidized
Cobalt-59 nuclear magnetic resonance Cobalt-59 nuclear magnetic resonance Cobalt-59 nuclear magnetic resonance is a form of nuclear magnetic resonance spectroscopy that uses cobalt-59, a cobalt isotope. Co is a nucleus of spin 7/2 and 100% abundancy. The nucleus has a magnetic quadrupole moment. Among all NMR active nuclei, Co has the largest chemical shift range and the chemical shift can be correlated with the spectrochemical series. Resonances are observed over a range of 20000 ppm, the width of the signals being up to 20 kHz. A widely used standard is potassium hexacyanocobaltate (0.1M KCo(CN) in DO), which, due to its high symmetry, has a