A 25.0 mL sample of 0.723 M HBr is titrated with a 0.273 M LiOH solution. The H3O+ concentration after the addition of 15.0 of KOH is ___________M

Answer 1

Use the formula for Molarity to determine the moles of H⁺ Ions and moles of OH^- ions then subtract the OH^-from the H⁺the resulting will be mole of H₃O⁺ divided by the total volume in liters will equal the [H₃O⁺].

0.025 x 0.723 = 0.018075 moles H⁺ ions; 0.015 x 0.273 = .004095 moles OH^- ions

0.018075 - .004095 = 0.01398/0.040 = 0.3495 M H₃O⁺ which is the H₃O⁺ concentration.