Question

Determine the pH during the titration of 58.1 mL of 0.411 M nitrous acid (Ka = 4.5×10-4) by 0.411 M NaOH at the following points. (Assume the titration is done at 25 °C.)

(a) Before the addition of any NaOH

(b) After the addition of 15.0 mL of NaOH

(c) At the half-equivalence point (the titration midpoint)

(d) At the equivalence point

(e) After the addition of 87.2 mL of NaOH

Answer 1

Answer :-

Firstly ionization equation is written for the nitrous acid then using the value of Ka and concentration, pH at every point is calculated.

The answer is given in the image,