The acidity of a water with initial pH of 5.5 was tested using the following procedure:
The pH of a volume of 50.00 mL water sample was adjusted to 4.0 using 5 mL 0.1 N H2SO4 solution. Then this sample was titrated using 0.2 N NaOH. After addition of 7 mL of 0.2 N NaOH, the pH of this water reached to 8.2. What is the acidity of the water sample express as CaCO3 in mg/L?
1 answer