In a solution,when the concentrations of a weak acid and its conjugate base are equal,________. A)the system is not at equilibrium B)the buffering capacity is significantly decreased C)the -log of the [H⁺] and the -log of the K_a are equal D)All of the above are true.

Question

Quizplus · Accepted Answer

When the concentrations of a weak acid and its conjugate base are equal, the solution is at its half-equivalence point. At this point, the -log of the [H⁺] and the -log of the K_a are equal, which is referred to as the pKa of the weak acid. At this point, the system is at equilibrium and has the maximum buffering capacity. Therefore, options A and B are false.

In a Solution,when the Concentrations of a Weak Acid and Its