Formula moleculara a alcanilor: CnH2n+2; μ =12n+2n+2, g/mol
in 100 g alcan sunt 82,75g C
in 14n+2 g alcan .... 12n gC 100x12n=82,75(14n+2) => n=4
CH3-CH-CH3 2METIL PROPAN
CH3
PRIN DEHIDROGENARE rezulta 2metil propena si H2
CH2=C(CH3)-CH3 +H2
PRIN CRACARE rezulta metan si propena
CH4 + CH2=CH-CH3