Fluorine

3 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Fluorine \Flu"or*ine\ (fl[=u]"[o^]r*[i^]n or fl[=u]"[o^]r*[=e]n;
     104), n. [NL. fluorina: cf. G. fluorin, F. fluorine. So
     called from its occurrence in the mineral fluorite.] (Chem.)
     A non-metallic, gaseous element of atomic number 9, strongly
     acid or negative, and associated with chlorine, bromine, and
     iodine, in the halogen group of which it is the first member.


     It always occurs combined, is very active chemically, and
     possesses such an avidity for most elements, and silicon
     especially, that it can neither be prepared nor kept in glass
     vessels, but may be contained in lead vessels. If set free it
     immediately attacks a containing glass vessel, so that it was
     not isolated until 1886. It is a pungent, corrosive,
     colorless gas. Symbol F. Atomic weight 19.00.
     [1913 Webster]
  
     Note: Fluorine unites with hydrogen to form hydrofluoric
           acid, which is the agent employed in etching glass. It
           occurs naturally, principally combined as calcium
           fluoride in fluorite, and as a double fluoride of
           aluminium and sodium in cryolite.
           [1913 Webster]

From WordNet (r) 2.0 [wn]:

  fluorine
       n : a nonmetallic univalent element belonging to the halogens;
           usually a yellow irritating toxic flammable gas; a
           powerful oxidizing agent; recovered from fluorite or
           cryolite or fluorapatite [syn: {F}, {atomic number 9}]

From Elements database 20001107 [elements]:

  fluorine
  Symbol: F
  Atomic number: 9
  Atomic weight: 18.9984
  A poisonous pale yellow gaseous element belonging to group 17 of the
  periodic table (The halogens). It is the most chemically reactive and
  electronegative element. It is highly dangerous, causing severe chemical
  burns on contact with flesh. Fluorine was identified by Scheele in 1771
  and first isolated by Moissan in 1886.