Define the Buffer capacity - Nutritional Biochemistry?

Buffer capacity can be defined as, 'the capacity of a solution to resist changes in pH on the addition of strong acid or strong base which may be expressed numerically as the number of moles of strong acid or strong base required to change the pH by one unit when added to one liter of the specified buffer solution'.

Thus,

Buffer Capacity (a) = The number of moles of H⁺ that must be added to 1 litre of the buffer in order to decrease the pH by 1 unit =  the buffer capacity in the acid direction, and

Buffer Capacity (b) = The number of moles of OH^- that must be added to one litre of the buffer in order to increase the pH by 1 unit = the buffer capacity in the alkaline direction.

Buffer capacity  as a quantitative unit for measuring buffering effects is therefore expressed as:

Buffering capacity =  δ (HA)/ δ  (pH)

Where δ is delta and HA is acid.

Buffer capacity is maximum when pH = pKa

With this basic understanding about buffers, we end our discussion about pH and buffers here. Next, let us get to know about the methods we can use for measuring pH.