C5H11

from The Collaborative International Dictionary of English v.0.48
Pentyl \Pen"tyl\, n. [Penta + -yl.] (Chem.)
   The hypothetical radical, {C5H11}, of pentane and certain of
   its derivatives. Same as {Amyl}.
   [1913 Webster]
    
from The Collaborative International Dictionary of English v.0.48
Amyl \Am"yl\, n. [L. amylum starch + -yl. Cf. {Amidin}.] (Chem.)
   A univalent hydrocarbon radical, {C5H11}, of the paraffine
   series found in amyl alcohol or fusel oil, etc.
   [1913 Webster]
    

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