The MSDS, of course, only mentions what you will find by analysis of the product, not what is put into the product. A considerable amount of KOH goes into the formation of the potassium aminophenolate. I do not know the pH of a solution that originally contained only enough KOH to make the p-aminophenol base soluble as the phenolate, but my attempts to make such a solution have measured in the 12-13 region. The 3% spec is surely an excess, not the total amount put in.
Originally Posted by Kirk Keyes
One can make a solution of KOH from K2CO3 and Ca(OH)2 in water. A slight excess of Ca(OH)2 would assure no carbonate in the solution, but perhaps a little of the calcium hydroxide. Any comment?