A #10.5*g# mass of a hydrocarbon contains #1.5*g# of hydrogen. If the molecular mass of the hydrocarbon in #210*g*mol^-1#, what are the empirical and molecular formulae of the hydrocarbon?
So the mol-ratio of
And the empirical formula is
One of those units has a mass of
So there are
We divide thru by the smallest molar quantity, and (clearly) we get an empirical formula of
But we know that the