Density of solution d (1g/L)
volume of solution(water) V
mass of H2SO4 dissolved = 2.1% of total mass of solution = 0.021dV
mass per litre of H2SO4 0.021dV/V = 0.021 * 1g/L
Normality of solution = mass perlitre of H2SO4 dissolved / equivalent weight of H2SO4 = 0.021 * 1 / 49 = 0.000486 N