Shelf Life of a Sodium Hydroxide Solution

Abstract

Of a 0.1 N NaOH solution, portions of about 400 ml were stored for four years in rubber-stoppered bottles of a) soft glass: b) Polyethene; c) Jena Geräteglas 20; d) Pyrex glass. Carbonate and total alkali (hydroxide + carbonate) contents were determined by titration, first to a phenol phthalein, afterwards to a chlorophenol red end-point. The results are listed in Table I, which also contains data for a freshly made solution.