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helium

more about helium

helium


  4  definitions  found 
 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
 
  Helium  \He"li*um\  (h[=e]"l[i^]*[u^]m),  n.  [NL.,  fr  Gr  "h`lios 
  the  sun.]  (Chem.) 
  An  inert,  monoatomic,  gaseous  element  occurring  in  the 
  atmosphere  of  the  sun  and  stars,  and  in  small  quantities  in 
  the  earth's  atmosphere,  in  several  minerals  and  in  certain 
  mineral  waters.  Symbol,  He  at  wt.,  4.  Helium  was  first 
  detected  spectroscopically  in  the  sun  by  Lockyer  in  1868;  it 
  was  first  prepared  by  Ramsay  in  1895.  Helium  has  a  density  of 
  1.98  compared  with  hydrogen,  and  is  more  difficult  to  liquefy 
  than  the  latter.  Chemically,  it  belongs  to  the  argon  group 
  and  cannot  be  made  to  form  compounds.  It  is  a  decomposition 
  product  of  the  radium  emanation. 
 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
 
  Helium  \He"li*um\,  n.  [NL.,  fr  Gr  ?  the  sun.]  (Chem.) 
  A  gaseous  element  found  in  the  atmospheres  of  the  sun  and 
  earth  and  in  some  rare  minerals. 
 
  From  WordNet  r  1.6  [wn]: 
 
  helium 
  n  :  a  very  light  colorless  element  that  is  one  of  the  six  inert 
  gasses;  the  most  difficult  gas  to  liquefy;  occurs  in 
  economically  extractable  amounts  in  certain  natural  gases 
  (as  those  found  in  Texas  and  Kansas)  [syn:  {He},  {atomic 
  number  2}] 
 
  From  Elements  database  20001107  [elements]: 
 
  helium 
  Symbol:  He 
  Atomic  number:  2 
  Atomic  weight:  4.0026 
  Colourless,  odourless  gaseous  nonmetallic  element.  Belongs  to  group  18  of 
  the  periodic  table.  Lowest  boiling  point  of  all  elements  and  can  only  be 
  solidified  under  pressure.  Chemically  inert,  no  known  compounds. 
  Discovered  in  the  solar  spectrum  in  1868  by  Lockyer. 
 
 




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