1. atomic number 14 a tetravalent nonmetallic element
  2. atomic number 10 a colorless odorless gaseous element that give a red glow in a vacuum tube; one of the six inert gasses; occurs in the air in small amounts
  3. atomic number 104 a radioactive transuranic element which has been synthesized
  4. atomic number 54 a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts
  5. atomic number 114 a radioactive transuranic element
  6. atomic number 11 a silvery soft waxy metallic element of the alkali metal group; occurs abundantly in natural compounds (especially in salt water); burns with a yellow flame and reacts violently in water; occurs in sea water and in the mineral halite (rock salt)
  7. atomic number 16 an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions)
  8. atomic number 18 a colorless and odorless inert gas
  9. atomic number 13 a silvery ductile metallic element found primarily in bauxite
  10. 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
  11. atomic number 12 a light silver-white ductile bivalent metallic element
  12. atomic number 17 a common nonmetallic element belonging to the halogens
  13. atomic number 24 a hard brittle multivalent metallic element
  14. atomic number 41 a soft grey ductile metallic element used in alloys
  15. atomic number 64 a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group
  16. atomic number 74 a heavy grey-white metallic element
  17. 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
  18. atomic number 15 a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms
  19. atomic number 19 a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
  20. atomic number 34 a toxic nonmetallic element related to sulfur and tellurium