Buffer Solution pH 7.0

Buffer Solution pH 7.0 To 1000 mL of a solution containing 18 g/l of disodium hydrogen phosphate R and 23 g/l of sodium chloride R add sufficient (about 280 mL) of a solution containing 7.8 g/l of sodium dihydrogen phosphate R and 23 g/l of sodium chloride R to adjust the pH (2.2.3). Dissolve in the solution sufficient sodium azide R to give a 0.2 g/l solution.