Element of the week: lead - video | @GrrlScientist

What do California condors, Beethoven and crime rates share in common?This week's element is lead, which has the atomic number 82 and the symbol Pb. Its symbol comes from the Latin word, plumbum, for lead. Lead rarely occurs in its elemental form in the wild. It is typically found in ores along with copper, and in smaller quantities with zinc and silver. Pure lead is a dense, soft and malleable metal with a lustrous bluish-white colour, although its surface quickly tarnishes to a dull grayish color in air. Lead is widespread and easy to work with, making it a popular material throughout the history of human tool-making. Lead has been used in all sorts of items ranging from a variety of pigments to car batteries and bullets. It was also commonly used in pipes for many hundreds of years, giving rise to the English words, "plumbing", "plumber", "plumb", and "plumb-bob" -- words derived from the same Latin root with lead. I even relied on lead bricks as shielding when radiolabeling DNA in the lab. Due to the large size and close packing of lead nuclei, they readily "absorb" gamma rays and x-rays, as well as alpha and beta particles (of course, a sheet of aluminium foil will also stop these particles). But lead doesn't stop all forms of radiation: the large size of lead nuclei makes it unsuitable for stopping neutron radiation, which can only be attenuated by atoms that have small nuclei. Biologists are interested in lead because it is so toxic to animals, although a single large ...
Source: Guardian Unlimited Science - Category: Science Authors: Tags: Blogposts guardian.co.uk Science Source Type: news