When 25.0 mL of sulfuric acid solution was completely neutralized in a titration with 0.05 M NaOH solution, it took 18.3 mL of the NaOH(aq) to complete the job. The reaction is:
NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + H2O(l)
What was the molarity of the sulfuric acid solution?



Answer :

Balanced equation will be as follows

2NaOH + H2SO4=Na2SO4 + 2H2O
from MaVa/MbVb=Na/Nb    where Ma is molarity of acid=?
                                                   Va is volume of acid=25.0 mL
                                                   Mb is molarity of base= 0.05 M
                                                   Vb is volume of base=18.3 mL
                                                    Nb number of moles of base= 2
                                                     Na is number of moles of acid =1

Ma*25 mL / 18.3mL*0.05M = 1/2
Ma=18.3*0.05M / 50 = 0.0183M


The molarity of sulphuric acid = 0.0183M