1. Plot potentiometric titration curves in pH–V coordinates. Determine the concentration of HCl, if the following results are obtained when titrating 20 ml of the analyzed acid solution with 0.10 N NaOH solution:
VNaOH, ml 10.0 18.0 19.0 19.9 20.0 20.1 21.0 22.0
pH 1.48 2.28 2.59 3.60 7.00 10.60 11.50 11.68