For a weak electrolyte such as acetic acid, the relation among conductance (λ), equilibrium constant (K) and concentration (C) can be expressed as: (λ^° is the conductance at infinite dilution)

Concept:

• For weak acid acetic acid, the dissociation is weak 
• If C is the initial concentration of acetic acid and  is the degree of dissociation, the equilibrium constant for the reaction can be expressed as;
•  can be expressed as 
• Where,  and  are the conductances at concentration C and zero.
• Putting the values of   in equilibrium constant we get,

Explanation:

• We know,  
• Rearranging this we can write
• Multiplying  on both sides we get
• Further rearranging this we can get 

Conclusion: -

For a weak electrolyte such as acetic acid, the relation among conductance (λ), equilibrium constant (K) and concentration (C) can be expressed as