Question

Be sure to answer all parts.

Calculate the pH during the titration of 40.00 mL of 0.1000 M HCl with 0.1000 M NaOH solution after the following additions of base:

(a) 20.00 mL

pH =

(b) 39.50 mL

pH =

(c) 51.00 mL

pH =

Answer 1

(a) 20.00 mL of 0.1000 M NaOH will neutralize 20 mL of 0.1000 M HCl.
40.00-20.00 = 20.00 mL of 0.1000 M HCl will remain.
Number of moles of HCl present moles
Total volume

(b) 39.50 mL of 0.1000 M NaOH will neutralize 39.50 mL of 0.1000 M HCl.
40.00-39.50 = 0.50 mL of 0.1000 M HCl will remain.
Number of moles of HCl present   moles
Total volume L

(c) 40.00 mL of 0.1000 M HCl will neutralize 40.00 mL of 0.1000 M NaOH.
51.00-40.00 = 11.00 mL of 0.1000 M NaOH will remain.
Number of moles of NaOH present moles
Total volume L