Creating Buffers: Salt or Acid/Base Pair?

[i_love_science]

Does there have to be both a salt and the conjugate acid/base of the anion/cation to create a buffer? Or can just a salt (e.g. ammonium formate) be a buffer?

Does a buffer require a salt that contains the same conjugate base as the acid, or not necessarily?

Thanks.

 

[Borek]

You need a conjugate pair, how you got it in the solution doesn't matter. You can start with an acid and a salt, you can start with the acid and partially neutralize it with some other base, you can start with just the salt and acidify it with some other acid.