Kohlrausch law
Kohlrausch law

source : AskIITians

Kohlrausch law-

According to this law,

” At infinite dilution , when ionisation is complete, each ion makes its contribution towards equivalent conductance ( or molar conductance) of the electrolyte and at infinite dilution equivalent or molar conductance is given by the sum of the equivalent  conductances of two ions (cations and anions).

Λ+m =  Λ0+    +    Λ0

Λ0+ = equivalent or molar conductance of cation at infinite dilution

Λ0 = equivalent or molar conductance of  anion at infinite dilution

Another form of  law,

Λ+m =  Λ0+  +    Λ0

+ and –  are number of cations and anions

Another form of Kohlrausch law,

Λm = Λ0m – K√ C

Λm = molar conductance

Λ0m = molar conductance at infinite dilution

K = Kohlrausch constt.

C = concentration


Λeq = Λ0eq – K√ C

Λeq  =  equivalent  conductance

Λ0eq  = equivalent  conductance at infinite dilution

” At low concentration for strong electrolyte , molar or equivalent conductance both vary linearly with square root of conductance”