An Erlenmeyer flask containing 20.0 mL of sulfuric acid of an unknown concentration was titrated with exactly 15.0 mL of 0.25 M NaOH solution to the second equivalence point. What was the concentration of sulfuric acid in the flask? H2SO4 (aq) + 2 NaOH (aq) → 2 H2O (l) + Na2SO4 (aq)

The concentration of sulfuric acid in the flask is  

Explanation:

The number of moles is mathematically defined as

  For the number of moles of NaOH substituting 15.0mL = for volume and 0.25M for concentration we have

From the balanced equation we can that the number of moles of required for this reaction is

Concentration is mathematically defined as            

Concentration of  

the answer is 0.8m.

by: nicholas