Relationship between normality and molar concentration is
Normality =n× molarity (M)
where, n= the number of moles of H+per mole of the compound that a solute is capable of releasing[acid] on reacting with base.
In case of HCl, n=1
Hence, 2NHCl solution ≈2MHCl solution In case of H2SO4, n=2
Hence, 4.0NH2SO4 solution ≈2MH2SO4 solution.