Karbonske kiseline (zadatak)

Submitted by aliasljubinko on Sat, 04/26/2014 - 19:29
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Koliko grama cinka se rastvara u 500cm3 20%  sircetne kiseline i koliko se cm3 vodonika (n.u) se razvija ( {\rho}= 1g/cm3).

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milicaradenkovic - Sat, 04/26/2014 - 21:16

Zn+2CH3COOH-------------------->(CH3COO)2Zn+H2

w=m/mr

mr=ro*V=500*1=500 g

m=mr*w=500*0.2=100 g

n=m/Mr=100/60=1.67 mol

n(Zn)=n(CH3COOH)/2=1.67/2=0.835 mol

m(Zn)=n*Mr=65*0.835=54.275 g

n(H2)=n(Zn)=0.835 mol

V(H2)=n(H2)*Vm=0.835*22.4=18.704 dm3=18704 cm3