Acid-Base Equilibria in Water Ostwalds Dilution Law

3 ACID-BASE EQUILIBRIA IN WATER OSTWALDS DILUTION LAW 

Consider the dissociation of a weak electrolyte, such as acetic acid, in dilute aqueous solution  

For simplicity above equation may be written in conventional manner as 

Hence the ion produced on dissociation are in equilibrium with the undissociated molecules of weak electrolytes in solution. Thus a weak acid solution of HA will have the equilibrium  

Where C is the concentration and a is the degree of dissociation. Applying law of mass action the dissociation constant of the acid is given by 

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