1. atomic number 52 a brittle silver-white metalloid element that is related to selenium and sulfur; it is used in alloys and as a semiconductor; occurs mainly as tellurides in ores of copper and nickel and silver and gold
  2. atomic number 53 a nonmetallic element belonging to the halogens
  3. atomic number 54 a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts
  4. atomic number 58 a ductile grey metallic element of the lanthanide series
  5. atomic number 25 a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals
  6. atomic number 12 a light silver-white ductile bivalent metallic element
  7. atomic number 22 a light strong grey lustrous corrosion-resistant metallic element used in strong lightweight alloys (as for airplane parts); the main sources are rutile and ilmenite
  8. atomic number 32 a brittle grey crystalline element that is a semiconducting metalloid (resembling silicon) used in transistors; occurs in germanite and argyrodite
  9. atomic number 82 a soft heavy toxic malleable metallic element
  10. atomic number 42 a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel
  11. atomic number 50 a silvery malleable metallic element that resists corrosion
  12. atomic number 51 a metallic element having four allotropic forms
  13. atomic number 55 a soft silver-white ductile metallic element
  14. atomic number 56 a soft silvery metallic element of the alkali earth group
  15. atomic number 57 a white soft metallic element that tarnishes readily
  16. atomic number 59 a soft yellowish-white trivalent metallic element of the rare earth group; can be recovered from bastnasite or monazite by an ion-exchange process
  17. atomic number 62 a grey lustrous metallic element of the rare earth group
  18. atomic number 72 a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons
  19. atomic number 92 a heavy toxic silvery-white radioactive metallic element
  20. atomic number 5 a trivalent metalloid element