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chemical properties 2Co + O2 = 2CoO Co + Br2
= CoBr2 2Co + N2 = 2CoN 3Co + C =
Co3C
Co + 2H2SO4 = CoSO4 + SO2 + 2H2O
2Co + 8CO = Co2(CO)8
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biological function Vital for the body trace element. It is
a part of vitamin B12 (cobalamin). It is involved in
blood formation, function of the nervous system and liver, enzymatic reactions. The human need for cobalt 0,007-0,015 mg daily. In the absence of cobalt akobaltoz develops.
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history of discovery 1923 French chemist Jean Urbain Danish chemist: Dirk Coster and
Georg de Hevesy
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physical properties silvery-white, having a surface with a bright
luster is not fading At ordinary temperatures it has a
hexagonal lattice Density = 13.09 g/cm3 (20 ° C) refractory metal, its melting temperature = 2222 ° C One of the rare natural isotopes of hafnium, 174Hf, exhibits a weak alpha activity (half-life of 2.1015 years)
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chemical properties Hf + 2F2 = HfF4 Other reactions that
occur under the influence of very high temperatures and
in practice. It also remains unclear their mechanism.