Proizvod rastvorljivosti

mariola's picture

U 12dm^3 H2O rastvoreno je 0.01g KBr i tom rastvoru je dodat 1cm^3 rastvora AgNO3 c=0.01mol/l.Da li ce doci do talozenja AgBr?Ksp(AgBr)=5 x 10-13

milicaradenkovic's picture

KBr+AgNO3----------------->AgBr+KNO3

n(KBr)=m/Mr=0.01/119=8.4*10(-5) mol

c1=n(KBr)/V=8.4*10(-5)/12=7*10(-6) mol/l

c2*V2=c1*V1

V2=12+0.001=12.001 dm3

c2=7*10(-6)*12/12.001=6.99*10(-6) mol/l KBr

V3=V2=12.001 dm3

c3V3=c4*V4

c4=0.01*1*10(-3)/12.001=8.33*10(-7) mol/l AgNO3

AgNO3------------------>Ag+ + NO3-

KBr----------------->K+ +Br-

c(Br-)=c2=6.99*10(-6) mol/l

c(Ag+)=c4=8.33*10(-7)

{Ag+}*{Br-}=8.33*10(-7)*6.99*10(-6)=5.82*10(-12)

posto je  {Ag+}*{Br-}>Ksp doci ce do talozenja AgBr