C=85.72/12=7.143 ||(14.28)==>0.5 atomi ||2 ==> 1 atom C
H=14.28/1=14.28 || (14.28) ==> 1 atom H ||2 ==> 2 atom H
Formula bruta (CH2)n=56==>14n=56==>n=4 ==> F.m C4H8 ->
NE=(2a+2)-(b-d+e)/2=(2*4+2)-8/2=10-8/2=2/2=1 leg. dubla
CH2=CH-CH2-CH3 --> 1-butena
CH3-CH=CH-CH3 --> 2-butena
CH3 H H H
C=C C=C 2-cis butena si 2-trans butena
H CH3 CH3 CH3
CH2=C(CH3)-CH3 --> 2-metil, 1-butena (izobutena)