Describe the difference between a strong acid and a weak acid?

A strong acid dissociates completely when you put it in water. So for example, if you put a certain amount of HCl in water, all of it will dissociate into H+ and Cl-A weak acid doesn't undergo full dissociation. So if you put a certain amount of something like CH3COOH (acetic acid) in water, only some of the acetic acid will dissociate into H+ and CH3COO-

It conforms what ever surface its in.