Weak Acid/Base Equilibria: C6H5OH & C6H5NH2 K_a & K_b

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C_6H_5OH, known as phenol, acts as a weak acid in water, while C_6H_5NH_2, or aniline, functions as a weak base. To derive the equilibrium expressions for their dissociation, one must first write the ionization reactions for both substances in water. The equilibrium constant expressions, K_a for phenol and K_b for aniline, can then be formulated. These expressions will include the concentration of water, which is constant and can be omitted from the final equations. The relationship between K_a and K_b is established through the concentrations of their respective conjugate base and acid. The discussion emphasizes the importance of showing work and understanding the initial steps in deriving these constants, while also providing resources for further clarification on dissociation constants and chemical calculations.
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C_6H_5OH acts as a weak acid and C_6H_5NH_2 acts as a weak base in water. Write equalibrium expressions for K_a and K_b.
 
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Hi my friend. What you should do here is write first the equilibrium reaction for these two substances ionisation in water, then deduce an expression for Kc-eqm constant. This expression will include the concentration of water, which is constant and thus cancels out of the equation. Then replace Kc by simply Ka or Kb, a new sort of equilibrium constant for these reactions. What you shoulb find is the Ka/Kb is simply the product of the concentrations of the conjugate base/acid and the new acid/base divided by the initial concentration of base/acid. Yours, Joe
 
First, show your work, if you had read the text you should at least know how to start.
 

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