Final answer:
To determine the molecular formula of a compound given its percent composition and molecular mass, we start by finding the empirical formula. In this case, the empirical formula is C4H5NO2 and the molecular formula is C8H10N2O4.
Step-by-step explanation:
To determine the molecular formula of a compound given its percent composition and molecular mass, we need to first find the empirical formula, which represents the simplest whole number ratio of atoms in the compound. To do this, we convert the percent composition into moles and find the smallest whole number ratio. Then, we calculate the empirical formula mass by summing the atomic masses of the elements in the empirical formula. Finally, we find the molecular formula by dividing the molecular mass of the compound by the empirical formula mass and multiplying the subscripts in the empirical formula by this factor.
In this case, the empirical formula for a compound with a percent composition of 49.47% C, 5.201% H, 28.84% N, and 16.48% O is C4H5NO2. The empirical formula mass is 99.1 g/mol. The molecular formula can be determined by dividing the molecular mass of 194.2 amu by the empirical formula mass of 99.1 g/mol, which gives a factor of 1.96. Multiplying the subscripts in the empirical formula by this factor, we get the molecular formula, which is C8H10N2O4.