<P> All elements of period 7 are radioactive . This period contains the actinides , which contains the heaviest naturally occurring element , plutonium ; subsequent elements must be synthesized artificially . Whilst the first five of these are now available in macroscopic quantities , most are extremely rare , having only been prepared in microgram amounts or less . The later , transactinide elements have only been identified in laboratories in batches of a few atoms at a time . </P>
<P> All elements of period 7 are radioactive . This period contains the actinides , which contains the heaviest naturally occurring element , plutonium ; subsequent elements must be synthesized artificially . Whilst the first five of these are now available in macroscopic quantities , most are extremely rare , having only been prepared in microgram amounts or less . The later , transactinide elements have only been identified in laboratories in batches of a few atoms at a time . </P>
what is the largest metalloid on the periodic table
what is the largest metalloid on the periodic table
plutonium
plutonium