Discovered in 1817, cadmium occurs in nature with zinc.
Cadmium is softer, more malleable and ductile than zinc. Chemically, it is less
reactive than zinc. Cadmium is obtained primarily from zinc smelters and from
the sludge produced by the electrolytic
refining of zinc. Removal of cadmium in zinc is very important since cadmium salts
are poisonous. Galvanized iron is used for water tanks and any residual cadmium
in the zinc would slowly enter the water reservoir as Cd2+ ions. Modern
day tanks show that there is no danger to health from this source. But older tanks
contain significant cadmium levels.
Cadmium and cadmium-containing compounds are used in a variety of ways. These
Cadmium and cadmium-containing compounds are used in a variety of ways. These include: