How to find the molecular formula from a empirical formula with subscripts that aren't whole numbers

Question

I am finding the formula of a compound that has 60% Carbon, 32% Oxygen, and 8% Hydrogen. Although, when it comes to actually creating the formula I end up with a subscript of 2.5 for C, 1 for O, and 4 for H.

I know I have to double each subscript for the empirical formula, but I am not sure what to do after that in terms of getting the molecular formula.

Answer 1

As written, you can't figure out the molecular formula

You need the molecular mass of the compound in order to determine the molecular formula.

The mass of the empirical formula (C₅H₈O₂) would be 90. If the molecular mass of the unknown were 90, then the molecular formula would be the same as the empirical formula; if the molecular mass of the unknown were 270, then you would divide 270/90 = 3 and that would be the multiplier for the molecular formula -- C₁₅H₁₆O₄.

But without the molecular mass, you can't determine the molecular formula.