Question

Question 5B: pH Changes Due to the"common ion effect," when the salt NaC3H,03 is added to an aqueous solution of the weak acid HC H,O3 will the following concentrations increase, decrease, or remain the same? b) HO c) IOH

Answer 1

HC₃H₅O₃ + H₂O $\Leftrightarrow$ C₃H₅O₃^- + H₃O⁺

This weakly acidic compound donate H⁺ and form C₃H₅O₃^- + H₃O⁺ ions. when we add C₃H₅O₃Na as a common ion, accodring to le chatliers principle when we increase the concentration of product side it tends to move opposite direction that means reactant side concentation increases so,HC₃H₅O₃ concentration increases.

next the equilibrium reaction move to backward direction so H₃O⁺ ion concentration decreases.

OH^- ion concentrations remains same or constant ,it doesnot change