Final answer:
The molecular formula of the compound with an empirical formula CH2O and a molar mass of 90.0 g/mol is C3H6O3, which is three times the empirical formula.
Step-by-step explanation:
If the simplest formula of a compound is CH2O and the molar mass of the compound is 90.0 g/mol, we can determine the molecular formula by comparing the empirical formula mass to the molar mass. The empirical formula mass of CH2O is 12.01 (carbon) + 2(1.01) (hydrogen) + 16.00 (oxygen) = 30.02 g/mol.
To find how many times the empirical formula mass fits into the molar mass, we divide the molar mass by the empirical formula mass: 90.0 g/mol ÷ 30.02 g/mol = 3. Therefore, the molecular formula contains three times the number of each atom present in the empirical formula. This gives us a molecular formula of C3H6O3.