I weighed 5.3240 g
Na2HPO4 and transferred it quantitatively into a 250 mL volumetric flask to which I added distilled (DI) H2O to the mark. I mixed the solution 20x by inversion.
I weighed 5.1750 g
H2NaHPO4.H2O and transferred it quantitatively into a 250 mL volumetric flask to which I added DI H2O to the mark. I mixed the solution 20x by inversion.
D. Preparation of 500 mL of 0. 076 M Sodium Phosphate Buffer, pH 7.0
I combined 97.5 mL
of 0.15 M NaH2PO4 (part A) and 152.5 mL
of 0.15 M H2NaPO4 (part B) in a 300 mL beaker and measured the pH. The pH was 6.96
so I transferred the solution to a 500 mL volumetric flask which I then filled to the mark with DI H2O. The pH was 6.99. I stored the buffer in the cold room.
