Question

What is the pH of a solution of vinegar, which is 5.00% (w/v) acetic acid (CH3COOH, Ka = 1.8 e-5).what is the % dissociation?

Answer 1

5.00% w/v acetic acid means 5.00 g acetic acid per 100 mL solution.
moles acetic acid = grams/molar mass = 15/60 = 0.25 moles/0.1 L = 2.5 M

Then CH3COOH --> H^+ + CH3COO^-

Ka = (H^+)(CH3OO^-)/(CH3COOH)
Set up an ICE chart and solve for H^+, then convert to pH.

%diss = [(H^+)/M]*100 = ??