Question

28.75 ml of 0.1720 N base is needed to titrate a sample of H2SO4 completely. How many grams of sulfuric acid were present? Show all work

Answer 1

Using conversion 1meq of base = 1 millimole  OH^-

meq of base = Normality x volume in mL = 0.1720 N x 28.75 mL = 4.945 millimole OH^-

H₂SO₄ + 2 OH^-      SO₄^2-   + 2H₂O

Millimole of H2SO4 = ( 1/2 ) x millimole of OH^- = 2.4725 Millimole

mole of H2SO4 = 2.4725 x 10^–3 mol H2SO4

Weight of H2SO4 = mol x molar mass = 2.4725 x 10^–3 mol x 98 gm mol^—1

= 0.24 gm H2SO4