Titel: Understanding Neutralization Reaction in Chemistry

How to calculate the volume of H₂SO₄ needed to reach the equivalence point when titrating NaOH?

23.7 mL of 0.269 M NaOH is titrated with 0.998 M H₂SO₄. How many mL of H₂SO₄ are needed to reach the equivalence point?

A. Approximately 9.8919 mL

B. Approximately 5.4321 mL

C. Approximately 12.3456 mL

Answer:

The correct answer is A. Approximately 9.8919 mL of 0.998 M H₂SO₄ is needed to reach the equivalence point when titrating 23.7 mL of 0.269 M NaOH.

Explanation: In a neutralization reaction, it is essential to find the volume of the acid required to neutralize the base completely. When titrating 23.7 mL of 0.269 M NaOH with 0.998 M H₂SO₄, we need to determine the volume of H₂SO₄ needed to reach the equivalence point.

To calculate this, we first find the moles of NaOH used by multiplying the molarity by the volume:

Moles of NaOH = Molarity × Volume = 0.269 M × 0.0237 L = 0.0063623 moles of NaOH

Since the balanced chemical equation shows that 1 mole of H₂SO₄ reacts with 2 moles of NaOH, we can then find the moles of H₂SO₄ needed, which is half the moles of NaOH:

Moles of H₂SO₄ required = 0.0063623 moles of NaOH / 2 = 0.0031811 moles of H₂SO₄

Next, we calculate the volume of 0.998 M H₂SO₄ required by dividing the moles by the molarity and converting it to milliliters:

Volume (L) = Moles / Molarity = 0.0031811 moles / 0.998 M ≈ 0.0098919 L

Finally, converting this to milliliters, we get:

0.0098919 L × 1000 mL/L ≈ 9.8919 mL

Therefore, approximately 9.8919 mL of 0.998 M H₂SO₄ is needed to reach the equivalence point when titrating 23.7 mL of 0.269 M NaOH, ensuring a complete neutralization reaction.