Acids in solution

[kristinalaudis3e]

Hello,

In lecture Lavelle stated that acid in a solution will be at pH 6. Does he mean the acid itself is at pH 6 or does he mean the solution will become pH 6?

[705383815]

pH refers to the concentration of H+ in a solution.

[Andreas Krumbein 1L]

The solution is at pH 6, since the way in which pH is measured is through the H₃O⁺ concentration, which requires that the water molecules ionize the H⁺ from the rest of the acid's molecular complex. Without being in solution, the H⁺ remains attached to the rest of the acid and no H₃O⁺ can be measured.

[Izamary Marquez 2H]

Also, I am a little confused on how we know whether it's 100% associated... Can we determine this based on the Lewis Structure of the molecule? In general, what does it mean for the acid to be "completely associated"?