Why does the buffer capacity reach a maximum when pKa pH?

The value of the buffer capacity is strongly related to the concentrations of ingredients used and increases with their increase. Buffer solutions with a pH equal to the pKa value of the acid (used to make this solution) have the greatest buffering capacity.

Why does the buffer capacity reach a maximum when?

A buffer consists of a weak acid and its salt or weak base and its salt. When the ratio of weak acid and its salt in a buffer (or the ration of weak base and its salt) is equal to 1, we say that the buffer capacity is maximum.

Does buffer capacity depend on pKa?

A solution with more weak acid, [HA], has a higher buffer capacity for the addition of a strong base. The buffer capacity is optimal when the ratio is 1:1; that is when pH = pKa.

What is the relationship between pH and pKa and the ability of the buffer to neutralize the addition of an acid or a base?

The lower the pH, the higher the concentration of hydrogen ions [H+]. The lower the pKa, the stronger the acid and the greater its ability to donate protons.

What is the effective pH range of a buffer?

Buffers are generally good over the range pH = pKa ± 1. The ammonia buffer would be effective between pH = 8.24 – 10.24. The acetate buffer would be effective of the pH range from about 3.74 to 5.74. Outside of these ranges, the solution can no longer resist changes in pH by added strong acids or bases.

What Conditions buffer capacity is maximum?

Buffer capacity of a buffer is maximum when the concentration of the weak acid and its salt or weak base and its salt are equal i.e., when pH=pKa or pOH=pKb.

How does the concentration of a buffer affect its buffer capacity?

The more concentrated the buffer solution, the greater its buffer capacity. If the buffer capacity is 10 times larger, then the buffer solution can absorb 10 times more strong acid or base before undergoing a significant change in pH.

What does it mean when pH is greater than pKa?

If the pH of solution is greater than the pKa, the group is in the conjugate base form (deprotonated). If the pH of solution is less than the pKa, the group is in the conjugate acid form (protonated).