Question

Calculate the molar concentration for H2SO4 in the following situation. When 54ml of it was completely titrated by 25ml of 1.2M NaOH, 1mol of acid was titrated by 2mol of base. Give your answer in two significant figures.

Answer 1

The molarity of the H₂SO₄ solution is calculated to be 0.28 M, after determining the moles of NaOH used in the titration and applying the stoichiometry of the reaction between sulfuric acid and sodium hydroxide.

Step-by-step explanation:

To calculate the molar concentration of H₂SO₄, we first need to determine the moles of NaOH used in the titration. Given that 25 mL of 1.2 M NaOH is used, we can multiply the volume by the molarity to get the moles of NaOH.

Moles of NaOH = Volume (L) × Molarity (M)

= 0.025 L × 1.2 M

= 0.03 mol NaOH

Since the reaction between sulfuric acid and sodium hydroxide shows that 1 mol of acid reacts with 2 mol of base, we can calculate the moles of H₂SO₄ as half the moles of NaOH.

Moles of H₂SO₄ = ½ × Moles of NaOH

= ½ × 0.03 mol

= 0.015 mol H₂SO₄

Finally, we calculate the molarity of the H₂SO₄ solution by dividing the number of moles by the volume in liters of the H₂SO₄ solution.

Molarity of H₂SO₄ = Moles of H₂SO₄ / Volume (L)

= 0.015 mol / 0.054 L

≈ 0.28 M

The molarity of the H₂SO₄ solution, to two significant figures, is 0.28 M.