I know that buffers have a capacity after which they are not able to maintain a relatively stable pH. This capacity is exceeded when we add too much acid or base but I was wondering why does this happen?
Suppose we have the buffer CH3COOH + CH3COONa If I were to keep adding HCl, the solution would actually lose its pH maintaining ability. Is it because when we add HCl, its H+ ions will start to get consumed by CH3COO- produced by the dissociation of CH3COONa and after some time, eventually, no CH3COO- ions to maintain the pH?
If this is the case then it means that the buffer solution actually has two capacities?
- The capacity to maintain pH after acid is added
- Capacity to maintain pH after base is added
Is this true?