CnH2n + HBr -->CnH2n+1Br
CnH2n + 5[O] -->Cn-1H2nO2 + CO2 +H2O
Daca prin oxidare se formeaza un acid si CO2(implicit si apa) inseamna ca alchena prezinta legatura dubla marginala.
M(compus bromurat)=14*n+81
14*n+81 g compus bromurat .................80 g brom
100 g .....................................................52,98 g brom
741,72n + 4291,38=8000
741,72=3708,62 => n=5
CH3-CH2-CH2-CH=CH3 1-pentena