# what is the pH of 5% vinegar?

i get a pH of .08 so something is wrong because I know it's at least 2. I took 50 grams per liter, and divided 50 by 60.05. And I did the negative log of that and got .08. Somebody please help!!!

Update:

5% acetic acid concentration of vinegar

Relevance

w(CH3COOH) = 5%

so n = 50 / 60.05 = 0.832 mol

since v=1L , c = 0.832 mol/L

Acetic acid is a weak acid (you cant calculate pH with the formula pH = -logc) so you need to know the constant of dissociation Ka which for acetic acid is 1.74 * 10^-5

Then you find pH according to the formula c(H+) = (Ka*c)^1/2

pH = (1/2)*pKa - (1/2)logc

pH = 0.5*(4.759) - [0.5*(-0.079)]

pH = 2.3795 + 0.0395

pH = 2.419

• Ph Of Vinegar

• Anonymous
9 years ago

The pH of vinegar depends upon how much acid is present, but most commercial distilled white vinegars contain 5% acetic acid and have a pH of about 2.4.

RE:

what is the pH of 5% vinegar?

i get a pH of .08 so something is wrong because I know it&#39;s at least 2. I took 50 grams per liter, and divided 50 by 60.05. And I did the negative log of that and got .08. Somebody please help!!!

Source(s): ph 5 vinegar: https://shortly.im/bpKee