The balanced equation is given as:
H2SO4+2NaOH→Na2SO4+2H2O
Molarity of NaOH=0.1M
Volume of NaOH=20cm3
Molarity of H2SO4=0.5M
mol NaOH = 0.1×20cm3=2molNaOH
⇒ 2molNaOH×2molNaOH1molH2SO4=1molH2SO4
volume of H2SO4=molarity of H2SO4mole of H2SO4
= 0.5M1mole=2cm3H2SO4