Carbonate-bicarbonate buffer (5X)
0.2 M anhydrous sodium carbonate (2.12 g/100 mL)
0.2 M sodium bicarbonate (1.68 g/100 mL)
Combine 4 mL of 0.2 M anhydrous sodium carbonate with 46 mL of 0.2 M sodium bicarbonate.
Bring to a final volume of 200 mL with H2O. The pH will be 9.2.
