Page 25 - Curriculum Visions Dynamic Book

For more on lead, see Volume 10: Lead and Tin in the Elements set.
to possible health hazards. Lead also goes
into plates for storage batteries, such as those in cars. Lead is an additive in lead glass, from which cut and crystal glassware are made. It is also an additive in special lenses.
Geology
Native lead is sometimes found as crystals
in hydrothermal veins close to old volcanic magma chambers. It more frequently appears as sulphide and carbonate compounds.Among the most common compounds are galena (lead sulphide, PbS) and cerussite (lead carbonate, PbCO3). Galena is the main mineral from which lead is refined.
Biology
Lead does not naturally occur in living things. However, when lead gets into the body, it affects the central nervous system and can cause brain damage. Lead does not easily
leave the body and builds up over the years. That is why small doses, such as are found in air polluted by leaded gas emissions, can be dangerous, especially for children.
Molten lead
 If an orange form of lead (ii) oxide (called litharge) is heated on a carbon block, it first turns yellow (a form of lead (ii) oxide called missicot) before being reduced
to molten lead. Colourless carbon monoxide gas is given off during the reaction.
 Lead is used as a shield against radiation.This laboratory chamber is used for handling radioactive materials and so has lead glass and solid lead walls.
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