Question

In the reaction H2SO4 + 2 NaOH -> Na2SO4 + 2H2O, an equivalence point occurs when 23.1 mL of 0.2055 M NaOH is added to a 25.0 mL portion of H2SO4. What is the [H2SO4]?

Answer 1

            moles NaOH = c · V = 0.2055 mmol/mL · 23.1 mL = 4.74705 mmol
            moles H2SO4 = 4.74705 mmol NaOH · 1 mmol H2SO4 / 2 mmol NaOH = 2.373525 mmol
Hence
            [H2SO4]= n/V = 2.373525 mmol / 25.0 mL = 0.09494 M
The answer to this question is  [H2SO4] = 0.09494 M