Cobalt By Selena Pineda

Facts Located on the periodic table, period 4 group 9 Symbol: Co Atomic number: 27 Atomic mass: 58.93 Transition metal

Atomic structure 27 protons 32 neutrons 27 electrons 4 energy levels, 2, 8,15,2

History Discovered by Georg Brandt in 1735 in Sweden Trying to demonstrate the blue color of glass The element is also found with bismuth

Found In In Geology Elements in the universe The sun Meteorites Earth's crust

Uses In Biology Abundance in humans Biological role Health hazards

Reactions of Cobalt Air; not reactive Water; little reaction Halogens; direct reaction Acids; dissolves slowly Cobalt is not particularly reactive with air. However on heating the oxide Co3O4 is formed. If the reaction is carried out above 900°C, the result is cobalt(II) oxide, CoO. Cobalt does not react directly with nitrogen, N2 . Water has little effect upon cobalt metal. The reaction between red hot cobalt metal and steam produces cobalt(II) oxide, CoO The dibromide cobalt(II) bromide, CoBr2, is made through the direct reaction between cobalt metal and bromine. Cobalt metal dissolves slowly in dilute sulphuric acid to form solutions containing the aquated Co(II) ion together with hydrogen gas, H2. In practice, the Co(II) is present as the complex ion [Co(OH2)6]2