A 0.5595 g sample of a compound containing C, H, and O was burned to produce 1.429 g CO2 and 0.5850 g H2O. If the molar mass of the compound was determined to be approximately 86.13 g/mol, what is its molecular formula?

I assume you know how to find the empirical formula since you obtained the right answer for C5H10O. The molecular formula is 86.13/empirical formula mass = x where is is the multiplier to be used on the empirical formula.

Just suppose the empirical formula mass is 42. Then 86.13/42 =2.051 which you would round to 2.0 and the molecular formula would be (CxHyOz)2 which will make the molecular formula
C2xH2yO2z
Post your work if you run into trouble.