An organic compound X contains 68.18% carbon 13.64%hydrogen and 18.18%oxygen .The relative formula mass of X=88.Given that C=12,O=16,H=1.Determine its molecular formula?

1 Answer
Jun 22, 2018

We got...#C_5H_12O#

Explanation:

As always, we assume a #100*g# mass of the material and interrogate its atomic composition...

#"Moles of carbon"-=(68.18*g)/(12.011*g*mol^-1)=5.68*mol.#

#"Moles of hydrogen"-=(13.64*g)/(1.00794*g*mol^-1)=13.53*mol.#

#"Moles of oxygen"-=(18.18*g)/(16.00*g*mol^-1)=1.14*mol.#

We divide thru by the LOWEST molar quantity to get an empirical formula of #C_((5.68*mol)/(1.14*mol))H_((13.53*mol)/(1.14*mol))O_((1.14*mol)/(1.14*mol))-=C_5H_12O#...

And here the empirical formula is the SAME as the molecular formula. How do I know?