To determine molecular formula, we first need to find out its empirical formula, Carbon. Hydrogen. Nitrogen. Oxygen Mass. 49.98g. 5.19g. 28.85g. 16.48g Mole. 4.165. 5.19. 2.06. 1.03 Divide 4. 5. 2. 1 by smallest So by comparing the mole ratio from the table above, i hope u understand the table The empirical formula is C4H5N2O given molecular mass = 194.19g so (C4H5N2O) n= 194.19 (48+5+28+16)n=194.19 n= 2 molecular formula = C8H10N4O2