Question

What is the molarity of a sodium hydroxide solution if 25.0 ml of this solution reacts exactly with 22.30 ml of 0.253 M sulfuric acid?

Thanks!

Answer 1

Number of moles of H2SO4 = Molarity x volume in L

                                                       = 0.253 M x (22.30/1000)L

                                                       = 0.00564 mol

The chemical reaction between H2SO4 and NaOH is as follows:

                        

    H₂SO₄ + 2NaOH  Na₂SO₄ + 2H₂O

1 mole of H₂SO₄ reacts with 2 moles of NaOH

0.00564 mol of H₂SO₄ reacts with M moles of NaOH

Mole of NaOH = ( 0.00564x2) / 1

   = 0.0113 mole of NaOH

So Molarity of NaOH , M = Number of moles / volume in L

                                     = 0.0113mol / (0.025 L

                                     = 0.452 M