Explain why the pH for a 02 M buffer system is 698 while tha

Explain why the pH for a 0.2 M buffer system is 6.98 while that same buffer diluted to 0.002 M is now has a pH of 7.19.

Solution

Remember dilution of buffer means that you dilute buffer by adding water but not some acid or base.
The pH of the buffer does not change when you dilute but the pH approaches neutrality i.e) pH will be
somewhere around or near 7, this happens because the buffer has to maintain acid-base equilibrium
during or after dilution.