Rastvori,stehiometrija

Sara9012's picture

Izracunaj masu CuSO4×5H2O koju treba rastvoriti u 300g vode da se dobije 15% rastvor CuSO4? 

Rjesenne: m(CuSO4×5H2O)=91.83

Marija 96's picture

w=m(CuSO4)/mr

mr=m(vode)+m(CuSO4*5H2O)

n(CuSO4)=n(CuSO4*5H2O)

m(CuSO4)=m(CuSO4*5H2O)*Mr(CuSO4)/Mr(CuSO4*5H2O)

m(CuSO4)=m(CuSO4*5H2O)*160/250

0.15=m(CuSO4*5H2O)*160/250*(300+m(CuSO4*5H2O))

0.15*300*250+250*0.15*m(CuSO4*5H2O)=160*m(CuSO4*5H2O)

11250=122.5*m(CuSO4*5H2O)

m(CuSO4*5H2O)=11250/122.5=91.83 g

Sara9012's picture

Marija,hvala puno