1. atomic number 4 a light strong brittle grey toxic bivalent metallic element
  2. atomic number 54 a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts
  3. atomic number 49 a rare soft silvery metallic element
  4. atomic number 47 a soft white precious univalent metallic element having the highest electrical and thermal conductivity of any metal; occurs in argentite and in free form; used in coins and jewelry and tableware and photography
  5. atomic number 40 a lustrous grey strong metallic element resembling titanium
  6. atomic number 1 a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
  7. atomic number 14 a tetravalent nonmetallic element
  8. atomic number 94 a solid silvery grey radioactive transuranic element whose atoms can be split when bombarded with neutrons; found in minute quantities in uranium ores but is usually synthesized in nuclear reactors; 13 isotopes are known with the most important being plutonium 239
  9. atomic number 43 a crystalline metallic element not found in nature
  10. atomic number 24 a hard brittle multivalent metallic element
  11. atomic number 41 a soft grey ductile metallic element used in alloys
  12. atomic number 64 a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group
  13. atomic number 74 a heavy grey-white metallic element
  14. atomic number 84 a radioactive metallic element that is similar to tellurium and bismuth; occurs in uranium ores but can be produced by bombarding bismuth with neutrons in a nuclear reactor
  15. atomic number 34 a toxic nonmetallic element related to sulfur and tellurium
  16. atomic number 42 a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel
  17. atomic number 44 a rare polyvalent metallic element of the platinum group
  18. atomic number 45 a white hard metallic element that is one of the platinum group and is found in platinum ores; used in alloys with platinum
  19. atomic number 46 a silver-white metallic element of the platinum group that resembles platinum; occurs in some copper and nickel ores; does not tarnish at ordinary temperatures and is used (alloyed with gold) in jewelry
  20. atomic number 48 a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc ores

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