niu, amestec = 89,6x10⁻³l/22,4l/mol= 10⁻³mol amestec
CH2=CH2 + Br2==> CH2Br-CH2Br
CH2=CH-CH3 +Br2===>CH2Br -CHBr-CH3
M=((2X12gC+4gH+2X80gBr)/mol= 188g/mol C2H4Br2
niu= 188x10⁻³g/ 188g/mol= 1x10⁻³mol C2H4Br2
Din prima ecuatie, rezulta 1x10⁻³mol CH2=CH2
4X10⁻³mol amestec......1x10⁻³ mol etena
100mol.........................25% etena-----> 75% propena