Sodium acetate and pH question

[grayfalcon89]

Hi,

 

This is from a part of solution from the list of problems I have to do for Analytical Chemistry class. This one line perplexes me, and I'm basically :doh:ing myself (smacking myself in the forehead..) because I can't understand it.

 

The question is to find the fraction of association ([math]\alpha[/math]) for [math]1.00 \times 10^{-12}[/math] M sodium acetate. Now, the solution says, "For [math]1.00 \times 10^{-12}[/math] M sodium acetate, pH = 7.00."

 

When I tried to use the equation for fraction of association, I ended up as x (the variable for [bH+] and [OH-]) as zero. Something isn't right, and I wonder if this is conceptual thing that I am missing out.

 

Sorry if this sounds like a homework. It's not. It's just one sentence that makes me confused on how you go from molarity to pH like that (and not just any pH, 7.00!).

[TheDrBraniac]

What is the fraction of association?