GCSE›AQA GCSE Chemistry›Mind mapsCrude Oil and HydrocarbonsAQA GCSE Chemistry: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsWhat is it?Finite resource found in rockA mixture of hydrocarbonsHydrocarbons contain only hydrogen and carbonMostly alkanes: CXnHX2n+2\ce{C_nH_{2n+2}}CXnHX2n+2Fractional distillationOil is heated until it evaporatesColumn is hotter at the bottomVapours condense at different heightsSeparates by boiling pointUsesFuels: petrol, diesel, kerosene, heavy fuel oil, LPGFeedstock for petrochemicalsMakes solvents, lubricants, polymers, detergentsCrude oilhydrocarbonsCHBigger moleculesBoiling point increasesViscosity increasesFlammability decreasesBurningPlenty of oxygen → complete combustionOnly CO₂ and water madeCHX4+2 OX2→COX2+2 HX2O\ce{CH4 + 2O2 -> CO2 + 2H2O}CHX4+2OX2COX2+2HX2OCX3HX8+5 OX2→3 COX2+4 HX2O\ce{C3H8 + 5O2 -> 3CO2 + 4H2O}CX3HX8+5OX23COX2+4HX2OExam tipsFlammability goes down with size, not upAlways balance combustion equationsSeparation is physical, no chemical reaction