2 What do I need to know?Recall how hydrocarbons can be cracked to make smaller more useful molecules.Describe some of the properties of alkenesExplain how alkenes can be used to synthesise polymers for a wide range of different applications.
3 Supply and demandOil companies have to balance supply and demand for the different fractions of crude oil.For example petrol may be higher in demand than diesel but the oil company may have less of it.How can they overcome these problems?
4 Supply and demand – the options Oil companies can make the fraction that is in demand more EXPENSIVEOil companies can lobby the Government to make changes to the system of TAXATION.Oil companies can make more of the fraction that is in demand, for example by CRACKING.
6 Catalytic CrackingThe larger fractions from crude oil can be of limited value as fuels or as chemical feedstock.To make these more useful and therefore more valuable they are split into smaller molecules using a process called CRACKING.
7 Heat the hydrocarbons to vaporise Pass over a hot catalyst OR Heat to high temperature with steamDecomposition then occursShorter alkenes and alkanes formed
15 Substances from Crude Oil PolymerisationSubstances from Crude Oil
16 What do I need to know?Recall the many different uses and applications of polymersDescribe how a polymer is made from monomers and how to draw monomers and polymersExplain the problems that are caused by polymers that are not biodegradeable.
17 PolymerisationIn polymerisation many small molecules MONOMERS join together to form a larger molecule POLYMER sometimes containing many thousands of monomers.
20 Uses of polymers Cling film/cellophane Non stick coating (Teflon) Tights and clothing (Nylon, Lycra)Windows and doors (uPVC)Bottles and food packagingWaterproof coatings for fabrics (Goretex)Dental polymersWound dressings especially for burnsHydrogels for use in nappies.Smart materials such as memory foam.
21 Waste disposal Many polymers are not biodegradeable This means they are not broken down by microbesThis can lead to problems with waste disposal
22 RemediesPlastic bags are being made from polymers and cornstarch so that they break down more easily.Biodegradeable plastic plastics are now widely used