Answer to Question #139407 in General Chemistry for jessica

Question

An average of 6.50 mL of 0.125 M of NaOH was required to neutralize 5.00 mL of an unknown H2SO4 solution. What is the concentration of the unknown H2SO4 solution?

Answer 1

The equation for this reaction is

2NaOH + H₂SO₄ --> Na₂SO₄ + 2H₂O

According to this equation, 2 moles of NaOH are required to neutralize 1 mole of H₂SO₄.

The amount of NaOH in moles equals $0.125M\times0.00650L=0.0008125mol$

Therefore, the amount in moles of H₂SO₄ equals $\frac{0.0008125}{2}=0.000406mol$, and the concentration is $\frac{0.000406mol}{0.00500L}=0.0812M$

Answer: 0.0812M