Question

What volume of 0.100 M HCl is required to titrate 25.0 mL of 0.050 M NaOH?

Answer 1

Number of mmoles of NaOH , n = Molarity x volume in mL

                                                 = 0.050 M x 25.0 mL

                                                 = 1.25 mmol

              NaOH + HCl NaCl + H₂O

According to the balanced Equation ,

1 mol of NaOH reacts with 1 mol of HCl

                             OR

1 mmol of NaOH reacts with 1 mmol of HCl

1.25 mmol of NaOH reacts with 1.25 mmol of HCl

We know that Molarity , M = number of mmoles / volume of solution in mL

Therefore volume of HCl required (mL) , V = Number of mmoles of HCl required / Molarity

                                                                    = 1.25 mmol / 0.100 M

                                                                    = 12.5 mL

Therefore the volume of HCl required is 12.5 mL