what is the chemical formula of petroleum? Share with your friends Share 0 Vasundhara Bissa answered this The chemical formula of petroleum is CnH2n+2 (combination of carbon and hydrogen). 6 View Full Answer Pradeep Ch answered this CnH2n+2hope it helps!!!cheers!!! 1 Pradeep Ch answered this thumbs up plzzz... 0 Madhurshalini Mahalingam answered this how do u no tat? 0 Madhurshalini Mahalingam answered this CnH2n+2.....cheers!!!!!i m great! 1