The balanced equation for the neutralisation reaction is as follows Ca(OH)₂ + H₂SO₄ ---> CaSO₄ + 2H₂O stoichiometry of Ca(OH)₂ to H₂SO₄ is 1:1 equivalent number of acid reacts with base number of H₂SO₄ mol reacting - 2 mol according to molar ratio of 1:1 number of Ca(OH)₂ mol = number of H₂SO₄ moles therefore number of Ca(OH)₂ moles required - 2 mol
