Question

Can I obtain the empirical formula from a elemental analysis of a sample?

Answer 1

Usually an elemental analysis will tell you that you have a certain number of grams of carbon, Hydrogen, and Oxygen, for example.
Using these masses, determine the number of moles present in each.

Then divide every elements moles by the element with the least number of moles.

For example, if you get C 4 moles, H 12 moles, and Oxygen 2 moles, set up something like this

C 4moles/2moles, H 12 moles/2 moles, and Oxygen 2moles/2moles

And you end up with ratios of C2H6O - or the formula for ethanol.