Formula generala alchene: C(n)H(2n)
Masa C(n)H(2n)=12n+2n=14n
1 mol H2.....2 g......22,4L=22,4dm^3
x g.......560cm^3=0,56dm^3
x=(2*0,56)/22,4=0,05 g hidrogen
Ecuatia
reactiei de aditie:
1,05 g 0,05g
CnH2n
+ H2 → CnH2n+2
14n 2
Aflam pe n: 1,05/14n=0,05/2
n=3
Alchena este C3H6 (propena) CH2=CH-CH3