Fossil Fuels

C.2.NoS Scientific community and collaboration—the use of fossil fuels has had a key role in the development of science and technology. (4.1)

Where fossil fuels come from

C.2.U1 Fossil fuels were formed by the reduction of biological compounds that contain carbon, hydrogen, nitrogen, sulfur and oxygen.

Three main categories of fossil fuel

C.2.AS4 Discussion of the advantages and disadvantages of the different fossil fuels.

C.2.G1 The cost of production and availability (reserves) of fossil fuels and their impact on the environment should be considered.

C.2.U6 Coal gasification and liquefaction are chemical processes that convert coal to gaseous and liquid hydrocarbons.

C.2.IM1 The choice of fossil fuel used by different countries depends on availability, and economic, societal, environmental and technological factors.

C.2.IM2 Different fuel rating systems (RON, MON or PON) are used in different countries.

C.2.IM3 Ocean drilling, oil pipelines and oil spills are issues that demand international cooperation and agreement.

C.2.Aims4 Aim 8: Consideration of the advantages and disadvantages of fossil fuels illustrates the economic and environmental implications of using science and technology.

Treatment and Conversion

C.2.U2 Petroleum is a complex mixture of hydrocarbons that can be split into different component parts called fractions by fractional distillation.

C.2.AS5 Identification of the various fractions of petroleum, their relative volatility and their uses.

C.2.U3 Crude oil needs to be refined before use. The different fractions are separated by a physical process in fractional distillation.

C.2.Aims1 Aim 6: Possible experiments include fractional distillation and catalytic cracking reactions

Cracking and reforming

C.2.U4 The tendency of a fuel to auto-ignite, which leads to “knocking” in a car engine, is related to molecular structure and measured by the octane number.

C.2.U5 The performance of hydrocarbons as fuels is improved by the cracking and catalytic reforming reactions.

C.2.AS1 Discussion of the effect of chain length and chain branching on the octane number.

C.2.AS2 Discussion of the reforming and cracking reactions of hydrocarbons and explanation how these processes improve the octane number.

C.2.AS3 Deduction of equations for cracking and reforming reactions, coal gasification and liquefaction.