Why are buffer solutions used to calibrate pH?

1 Answer
Apr 25, 2015

Buffer solutions are used to calibrate pH meters because they resist changes in pH.

When you use a pH meter to measure pH, you want to be sure that if the meter says pH = 7.00, the pH really is 7.00.


So you use solutions of known pH and adjust the meter to display those values.

Buffers are ideal for this purpose because:

  • They are easily prepared for a given pH.
  • They are stable for long periods of time.
  • They resist changes in pH if you accidentally add a little acid or base or even water.