Question

A 15.00 mL solution of H2​SO4​ was titrated with 1.75MNaOH. If it took 6.50 mL of NaOH to reach the equivalence or stoichiometric point, what is the molarity of H₂​SO₄​ solution?

H₂​SO₄​​ and NaOH react according to the following equation.
H₂SO₄​​+2NaOH→2H₂O+Na₂​SO₄​

Answer 1

To find the molarity of the H₂SO₄ solution, calculate the moles of NaOH used in the reaction, deduce the moles of H₂SO₄ from the stoichiometric ratio, and then divide by the volume of the H₂SO₄ solution. The molarity of the given H₂SO₄ solution is 0.37917 M.

Step-by-step explanation:

To calculate the molarity of the H₂SO₄ solution, you firstly need to determine the moles of NaOH used in the titration. This is done by multiplying the concentration of NaOH by its volume in liters. Once you have the moles of NaOH, you can use the chemical reaction stoichiometry to find out the moles of H₂SO₄ that reacted, which is half the amount of NaOH since the molar ratio of H₂SO₄ to NaOH is 1:2.

Here are the steps to calculate the molarity of the H₂SO₄ solution:

1. Calculate the moles of NaOH: (Volume of NaOH in L) × (Molarity of NaOH) = Moles of NaOH
2. Using the balanced chemical equation (H₂SO₄ + 2NaOH → 2H₂O + Na₂SO₄), determine the moles of H₂SO₄ (Moles of NaOH × 1/2).
3. Calculate the molarity of H₂SO₄: Moles of H₂SO₄ ÷ Volume of H₂SO₄ solution in liters = Molarity of H₂SO₄

Now, we apply this to the given data:

• Moles of NaOH = 0.0065 L × 1.75 M = 0.011375 moles
• Moles of H₂SO₄ = 0.011375 moles × 1/2 = 0.0056875 moles
• Molarity of H₂SO₄ = 0.0056875 moles ÷ 0.015 L = 0.37917 M