PH a pH of 7.3. This is clearly wrong as an acid solution should have a pH of less than 7. Treating the system as a mixture of hydrochloric acid and the amphoteric substance water, a pH of 6.89 results. A weak acid or the conjugate acid of a weak base can be treated using the same formalism. First, an acid dissociation constant is defined as follows. Electrical charges are omitted from subsequent equations for the sake of generality and its value is assumed to have been determined by experiment. This being so, there are three unknown concentrations, [HA], [H] and
Thioglycolic acid also used in so-called "fallout remover" or "wheel cleaner" to remove iron oxide residue from rims. Ferrous iron combines with thioglycolate to form red-violet ferric thioglycolate. Thioglycolic acid is prepared by reaction of sodium or potassium chloracetate with alkali metal hydrosulfide in aqueous medium. It can be also prepared via the Bunte salt obtained by reaction of sodium thiosulfate with chloroacetic acid: Thioglycolic acid is about 100 times stronger acid than acetic acid with a pKa of 3.83: The second ionization has a pKa of 9.3: Thioglycolic acid is a reducing agent, especially at higher pH. It oxidizes to the