It is an online assignment and it says it is wrong. I have tried it two different times now and got the answer of .0012432355 both times and it is wrong.
Concentration of lead = .0012432355
Concentration of iodide = .003508607
ionic strength = .00474
activity of lead = .74557681557...
The debeye huckel equation: log(\gamma)=(-0.51z^2\sqrt{}I)/(1+[(a\sqrt{}I)/305]
Where: gamma is the activity coefficient. z is the charge of the ion. I is the ionic strength of the solution. a is the ion size parameter, which is 450 for lead and 300 for iodide.
Homework Statement
Find the concentration of Pb2+ in 0.0010 M KI with PbI2. Include activity coefficients in your solubility-product expression. The Ksp of PbI2 is 9.8*10^-9
Homework Equations
Ksp= [Pb2+]\gammaPb2+[I-]2\gamma2I-
Assume that [I-]=0.0010 M. The ionic strength of 0.0010 M Ki...
Homework Statement
Two identical atoms in a diatomic molecule vibrate as harmonic oscillators. However, their center of mass, midway between them, remains at rest.
1)Show that at any instant, the momenta of the atoms relative to the center of mass are p and -p
2)Show that the total...
Nevermind I got it. The pivot was exerting a force upwards on the ladder, so had to change my pivot point to the bottom of the ladder and redo the sum of the torques. I then could cancel out the cos and solve for the missing force The answer was 645.8 N. Thanks for the help.
Ok, so the only force acting in the x direction is the force of the pivot on the ladder (F_Nx).
Sum of forces in y= 1000N - F_Ny(force of alley on ladder)
Sum of torques around the pivot= (4m)(250N)(cos\vartheta)+(1.5m)(750N)(cos\vartheta) -(6m)(F_Ny)(cos\vartheta)=0
I canceled out the...
Homework Statement
A nonuniform fire escape ladder is 6.0 long when extended to the icy alley below. It is held at the top by a frictionless pivot, and there is negligible frictional force from the icy surface at the bottom. The ladder weighs 250 , and its center of gravity is 2.0 along the...