Question

If the mole fraction of nitric acid (HNO3) in an aqueous solution is 0.275, what is the percent by mass of HNO3?

Answer 1

Molar mass of    N    = 14 g/molMolar mass of   O2    = 32 g/molAdding both masses = 46 g/molActual molar mass/ Empirical molar mass = 138.02 / 46 = 3Now multiplying this co effecient with empirical fomula NO2 = 3(NO2)                                                                                             = N3O6So according to above explanation,D) N3O6, is the correct answer.