[Ann1234]

Hello!

I am doing some buffer problems but I am stuck on this - let's say we have to prepare a buffer acetate 0.1M; does it mean...

1) (ion acetate) = 0.1M
2) or (acetate ion) + (acetic acid) = 0.1M?

I found several solved problems online using these 2 approaches so I was wondering if anyone can clarify this for me - thank you! 

[JustinCh3m]

buffers contain a weak acid and a salt of it's conjugate base (in your case).  So which one?  Number 1 or Number 2?

[Ann1234]

This is the problem: "you have to prepare one liter of solution 0.1 M of acetate buffer.
For this preparation: you have a solution 0.1M of acetic acid and another solution 0.1 M of sodium acetate. How do you prepare this buffer?"

My question is- do I assume the final acetate concentration is 0.1M (in the buffer) or the sum of both acetic acid + acetate ion = 0.1M? that's my confusion...

addition: Ph of the buffer needs to be 4.76
PKa HAc = 4.76

[Borek]

2) or (acetate ion) + (acetic acid) = 0.1M?

Bingo.

[Ann1234]

2) or (acetate ion) + (acetic acid) = 0.1M?

Bingo.

That is exactly what I wanted to know - thanks!!!