Heavy metals facts for kids

Crystals of osmium, a heavy metal nearly twice as dense as lead.

Heavy metals are metals or chemical compounds containing metals, which are a concern to the environment. This definition was made, when the effects of cadmium, mercury and lead became known. All of these are denser than iron. The definition has since been applied to any other similarly toxic metal, or metalloid such as arsenic, regardless of density. Commonly encountered heavy metals are chromium, cobalt, nickel, copper, zinc, arsenic, selenium, silver, cadmium, antimony, mercury, thallium and lead. More specific definitions of a heavy metal have been proposed; none have obtained widespread acceptance.

Images for kids

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  In a cello (example shown above) or a viola the C-string sometimes incorporates tungsten; its high density permits a smaller diameter string and improves responsiveness.

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  Neodymium sulfate (Nd2(SO4)3), used to colour glassware

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  The Topaz Solar Farm, in southern California, features 9 million cadmium-tellurium photovoltaic modules covering an area of 25.6 square kilometres (9.5 square miles).