Alkeni

Submitted by Hemicarka5 on Mon, 12/01/2014 - 23:27
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Gasoviti alken zapremine 100cm3 ima masu 0,233g;25cm3 ovog alkena reaguje sa 25cm3 vodonika.
a)Nadjite molarnu masu alkena
b)Napisite njegovu molekulsku formulu

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milicaradenkovic - Tue, 12/02/2014 - 07:54

a) CnH2n+H2-------------->CnH2n+2

n(CnH2n)=V/Vm=100*10(-3)/22.4=0.004464 mol

Mr=m/n(CnH2n)

Mr=0.233/0.004464=52 g/mol

Mr=n*Ar(C)+2n*Ar(H)

52=12*n+2*n*1

52=14*n

n=52/14=3.7 sto je bilu 4 i to je buten

b0 CH3CH2CH=CH2