selenium Se atomic number 34
selenium%1:27:00:: se%1:27:00:: atomic_number_34%1:27:00::
se selen
a toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite)