A buffer is prepared using the conjugate acid-base pair acetic acid and acetate ions. Write chemical equations showing the reactions that take place when H+ and OH- are added to the buffer.
CH3COOH + OH- > CH3COO- + H2O AND CH3COO- + H+ > CH3COOH
Buffer: CH3COONa and CH3COOH CH3COONa exists as CH3COO- since it is a string electrolyte. now CH3COOH is in equilibrium CH3COOH-> CH3COO- + H+. So let us say you add an acid. Now since H+ concentration increases, The equilibrium proceeds in the reverse direction(Le Chateliers Principle). So the reaction(Actually the equilibrium shifts) is CH3COO- + H+ -> CH3COOH. Now less acid dissociates and hence Ph is maintained. Now let us add a base. H+ + OH- -> H2O. Neutralization occurs. Now H+ concentration reduces in the mixture This shifts the equilibrium to the right again Le Chatleliers principle. So Now the reaction becomes CH3COOH-> CH3COO- + H+ . Now more H+ is being produced so the Ph is Unchanged.
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