Why can Fractional Distillation work with Crude Oil?

-As the Mixture is heated up, the Molecules have more Energy and can move About -A Molecule may eventually be able to Overcome the Intermolecular Forces, making it a Gas -However, the Covalent Bonding still remains, as it needs more Energy to Overcome -And that's why the Smaller Hydrocarbons are the Easiest to break off, as they have less Points to have Intermolecular Forces compared to bigger Hydrocarbons C₄₅H₉₂ [This gives them their Higher Boiling Points