Rastvori

nixahemicar's picture

Izracunati zapremine 7,7% rastvora H2SO4, gustine 1,05g/cm3 i 20,1% rastvora iste kiseline, gustine 1,14 g/cm3, potrebne za dobijanje 100cm3 12%-tnog rastvora.

milicaradenkovic's picture

V1*c1+c2*V2=c3*V3

c1=n1/V1=ms1/Mr*V1=w1*mr1/Mr*V1=w1*ro1/Mr=0.077*1.05*1000/98=0.825 mol/l

c2=w2*ro2/Mr=0.201*1.14*1000/98=2.338 mol/l

ro3=ro1+((w3-w1)/(w2-w1))*(ro2-ro1)

ro3=1.05+((0.12-0.077)/(0.201-0.077))*(1.14-1.05)=1.0812 g/cm3

c3=ro3*w3/Mr=1.0812*1000*0.12/98=1.3239 mol/l

V1*0.825+V2*2.338=100*1.3239

V1+V2=V3

V1=V3-V2

0.825*(100-V2)+2.338*V2=100*1.3239

82.5+1.513*V2=132.39

49.89 =1.513*V2

V2=49.89/1.513=32.97 cm3 20.1% kiseline

V1=100-32.97=67.03 cm3 7.7% kiseline