Final answer:
To determine the molecular formula of a compound from its decomposition products, you must first calculate the moles of NO2 and H2O produced, then convert these into moles of the constituting elements. Finally, the empirical formula is found and scaled using the molar mass to get the molecular formula.
Step-by-step explanation:
The question asks how many moles of NO2 are required to produce a given number of moles of oxygen and hydrogen, and to determine the molecular formula of a compound. To find the number of moles, the molar mass of NO2 is used. By using the mass given for NO2 and H2O, one can use stoichiometry to determine the molecular formula of the initial compound.
Given the mass of NO2 and H2O, the moles of Nitrogen, Hydrogen, and Oxygen are first calculated based on their respective molar masses. Using the molar mass of the sample (78.5 g/mol), the empirical formula can be calculated, which then can be scaled to find the molecular formula.