Selecting the best buffers to reach a pH of 8?

[Violagirl]

I am trying to figure out how you would select a good buffer to use to reach a pH of 8 and it will need to be a 0.1 M solution for a lab experiment I'll doing for class this week. I've been given a list of possible buffer salts to select and then will need to add either HCl or NaOH to get to my pH. The question I have, how do you best tell?

For example, for one choice, I need to choose between Citrate or Phosphate. I know both are polyprotic (each have 3 pKas). Would using the Hendersen-Hasselbalch equation come in handy for this? I've read that a good buffer will be within one value of your desired pH but wanted confirmation on this.

So if I were to take Citrate and incorportate one of its pKas into an equation, I'd get:

pH = pKa - log [HA]/2

pH = 4.74 + log [0.1]/2 = 3.74

Is this the right way to figure out what buffer you'd want to select for polyprotic buffer?

Otherwise, my other buffer choices are between acetate, CAPS, HEPES, Tricine, or TRIS. Thanks so much for reading!