How to explain that pH doesn't change?

If a buffer solution is formed from acetic acid (HC2H3O2) and the acetate ion (C2H3O2-), and you write the 2 equations:

(a) for the reaction that occurs when an acid is added to this solution

and

(b) for the reaction that occurs when a base is added to this solution.



How can I explain that pH does not change?How to explain that pH doesn't change?
The pH does change, but it's just by a small amount. The reason is that only a small fraction of the buffer acid is ionized, and thus adding a little bit of acid or base only causes a slight change in the molarity of conjugate base. in other words, the ratio of the total molarity of buffer to that of the conjugate base is very large thanks to the small Ka value, so there's a sizeable reservoir of buffer weak acid.How to explain that pH doesn't change?
I do remember that pH does not change when using buffers because buffers helps maintain homeostasis within a system.
It's all about buffering capacity!

study your chemical reactions and learn them on your own.
pH in and of itself is only an indicator of whether a substance is acidic or basic with water standard at 7 in the middle of a scare from 1 thru 14. (1 thru 6=acidic); 8 thru 14=basic

And acid plus a base will yield a salt plus water.