In layman's terms, what is the difference between unbuffered and buffered water?

Question

And what can act as a buffer?

Answer 1

A buffered solution maintains its pH despite additions of acid or base (over a range) while the pH of an unbuffered solution will respond to modest additions of acid or base. For details see the Wikipedia article:

http://en.wikipedia.org/wiki/Buffer_solu...

Answer 2

A buffer is something that regulates the pH of a solution.

So buffered water will resist changing its pH i.e. add an acid to it and its pH shouldn't change.

Unbuffered water is the opposite i.e. normal water.

Answer 3

a buffred system means one that resists a change in pH when an acid or base is added to the solution. Water is not buffered because the addition of acid will lower the pH , addition of base will raise the pH because of the relationship ..that pH + pOH = 14. A buffer will prevent such pH changes because a buffer system is composed of a weak acid and its conjugate base....so that when a strong acid like HCl is added  the H+ from the HCl will react with the base form in the buffer making the weak acid  which is weak because lttle of the acid is ionized ( which means very little H+ is produced ). If a strong base is added  ( like OH-1 ) that will react with the weak acid  making more of the conjugate base which is a weaker base than OH and thus have minimal effect of raising the pH.