Question

* Glycerol contains 39.1%. Carbon and 52.27. oxygen , with the remainder being hydrogen. What is the empirical formulae of glycerol?​

Answer 1

Answer:

As always, we ASSUME an 100∙g mass of stuff, and we interpolate the molar quantities by dividing each mass thru by the ATOMIC mass of each element.

ncarbon=39.1∙g12.01∙g∙mol−1=3.26∙mol

noxygen=52.27∙g16.0∙g∙mol−1=3.26∙mol

nhydrogen=8.7∙g1.0∙g∙mol−1=8.7∙mol

We divide thru by the LEAST molar quantity to get a trial empirical formula of CH2.7O . But the empirical formula specifies whole numbers, so we multiply by three to get C3H8.1O3 . And this is near enuff the empirical formula of glycerol. Of course, the molecular formula is some WHOLE NUMBER multiple of the empirical formula. And here that multiple is ONE, given the molecular mass quoted in the boundary conditions of the question.