[coolengineer]

I need to predict the conductivity of a solution using Kohlrausch's law. Basically here's the problem:
I have some amount of starting solution - lets say 65 Kgs with a strong electrolyte in it. I need to add some amount of Water to it to bring down the conductivity from a starting value of around 22mS/cm to about 17 mS/cm.
I have data points from past experiments that were done using trial and error methods by adding the water manually until the conductivity meter showed the desired conductivity.So I have the following data

1) Initial mass of the solution (m1)
2) Initial conductivity (k1)
3)Final mass of the solution (m2)
4)Final conductivity of the solution (k2)
5) The amount of water added (m2-m1)

I need to justify these values using Kohlrausch's law. Using the equations, I derived => k2-k1 = K[(c1)^.5 - (c2)^.5]
Since we're only adding water, moles of salt would be constant..so we can factor it out and replace the volume by mases.
k2-k1 = K*n [(1/V1) - (1/V2)]
Using these equations, I am still not getting the answer.
Help please?

[Borek]

k2-k1 = K[(c1)^.5 - (c2)^.5]

k2-k1 = K*n [(1/V1) - (1/V2)]

No idea how you got first, no idea how it is related to second.

But I also have no idea what you are trying to do. As long as initial and final conductivities are identical each time, simple ratio should do. Or are conductivities different now?