Alcadienele raspund la formula CnH2n-2
=> 14n-2 = 82 => n = 6 , hexadiena
stereoizomeri = iz. optici + iz. geometrici
C-C=C-C=C-C cis-cis + cis-trans + trans-cis + trans-trans
C=C-C=C(C)2 cis + trans
C=C-C=C-C-C cis + trans
C=C(C)-C=C-C cis + trans
C=C-C(C)=C-C cis + trans
=> 12 izomeri