It takes a fair amount of change in amount of borax to make a change in pH of a solution of borax. However, the concentration of borax has a greater effect on local dynamic changes in pH than will be seen after equilibrium is reached. Frankly, I am not one to quibble, as PE will testify. However, the difference in number of molecules between 2 grams each of penta- and decahydrate is about 30%, so if you had all penta and thought it was decahydrate, you would be getting the equivalent of 2.62 grams of the specified decahydrate. Would that make a visible difference in the output of D-76? It depends on how sensitive you are to such things. I take it that the purification process would be worth while if one could not buy the Photo grade stuff, of PE and Kirk Keyes would not chastise me for trying to put Photo Formulary out of business by doing it.
Originally Posted by Murray Kelly