8.1.1 Alternatively, this solution may be purchased from a commercial vendor and its exact molarity shall be determined in accordance with 10.1
8.2 Aqueous sulfate standard,0.01 M -Dry 5 g anhydrous sodium sulfate at 110 c for 1 h . Remove it from the oven and allow it to cool in a desiccator over anhydrous calcium sulfate. Accurate weigh about 0.70 g on an analytical balance to the volumetric flask. Add Type III water to dissolve the sodium sulfate then dilute to volume. Calculate the exact concentration in accordance with Eq1