Chemistry 5 cracking hydrocarbons gcse core flashcards. A lesson covering cracking hydrocarbons as part of the organic chemistry unit key stage 4, aqa. Petrochemicals and polymers, petroleum, alternative fuels and energy sources, addition polymerisation, condensation polymerisation. Cracking creates more useful hydrocarbons from less useful hydrocarbons by breaking down long chain alkanes into shorter chain molecules of alkane and alkene. Apart from alkenes and alkanes what else is made during the process of cracking.
Targeted towards aqa c1 topic 5 but suitable for edexcel and other exam boards too. The process is done at high temperature and pressure. Cracking is the name for processes which breaks long hydrocarbon molecules into shorter ones. Cracking is used to convert long alkanes into shorter, more useful hydrocarbons. Cracking is important because cracking produces shorter chain saturated hydrocarbons which are more in demand as fuel and unsaturated hydrocarbon which is used in polymer synthesis. The complete combustion of a hydrocarbon produces carbon dioxide 1 mark and water 1 mark.
Lesson with option of differentiated resources for cracking hydrocarbon fuelsfractions. Are larger hydrocarbons more or less viscous than smaller hydrocarbons. Catalytic cracking takes place at a slight pressure, high temperature and in the presence of a zeolite catalyst and is used mainly to produce motor fuels and aromatic hydrocarbons mechanism not required. If the answer you have written is not right, change it. Cracking and alkenes crude oil, hydrocarbons and alkanes. Designed by expert teachers for the edexcel gcse 91 chemistry syllabus. After the fractional distillation of crude oil there are too many large hydrocarbons and not enough small hydrocarbons to meet the publics demand. Alkenes along with alkanes can be produced from cracking. Cracking hydrocarbons edexcel gcse chemistry revision notes. Petrol and other fuels are produced from it using fractional distillation. During cracking, hydrocarbons are often passed over a substance so that they break apart. During combustion, the and in the fuels are oxidised. Your students can be examready with this fantastic resource. Top 5 college degrees that are actually worth it 2020 duration.
This lesson was originally designed for the aqa gcse 91 chemistry specification but is easily transferable to other specifications including ks3 as a challenge lesson and ks5 as a recap lesson. The complete series covers the aqa gcse 91 chemistry 8462 and combined science trilogy 8464 specifications for chemistry. Give an example of a method by which cracking can be carried out. Model the industrial process of cracking larger hydrocarbons to produce smaller alkanes that can be converted into petrol. In addition to this you will need to know about functional groups such as alcohols, carboxylic acids and esters and how to draw their structures. There is a greater demand for smaller hydrocarbons than larger ones. To make long chain hydrocarbons into shorter more useful hydrocarbons. You need to know about alkanes, alkenes, crude oil and the process of cracking. Furthermore, it should be treated in order to obtain highly effective end products.
Igcse chemistry past exams, tutorials, notes and more on nada ak is lecturing us some seriou. Cracking hydrocarbons in liquid paraffin with a catalyst. It is caused by the breaking of carboncarbon bonds. See also the dehydration of ethanol to produce ethene. Gcse chemistry revision science section covering cracking and its products, hydrocarbons, catalyst, thermal decomposition, alkanes, single and double covalent bonds, and cracking paraffin. This summarises the key topics for the organic chemistry unit, including crude oil, the structure of alkanes, fractional distillation, properties of hydrocarbons, cracking, alkenes and polymerization. The unit then moves onto the alkenes as a different homologous series from the alkanes, together with a consideration of the cracking process. Cracking meaning types of cracking organic chemistry. Two methods of cracking how to write a balanced equation for cracking what an alkene is, and how they differ from an alkane the test for alkenes the. Cracking is defined as a process, wherein complex organic molecules namely long chain hydrocarbons or kerogens are broken down into smaller molecules namely light hydrocarbons. The best way to remember the information in this chapter is to get a pen and paper and write down your answers before clicking on the answer link which will take you to the correct page you may have to read through some of the page before you find the answer. Written by teachers for the edexcel igcse chemistry course. This resource is a broken down practice exam question to help improve exam technique when answering exam questions on cracking hydrocarbons.
Since crude oil is a mixture of different components, it should be processed to obtain a better product that has no impurities. During combustion, the carbon 1 mark and hydrogen 1 mark in the fuels are oxidised. A hydrocarbons are broken down 1 mark to produce smaller more useful molecules 1 mark. Gcse science chemistry 91 combustion of hydrocarbons duration.
Fuels made from oil mixtures containing large hydrocarbon. Gcse chemistry revision questions fossil fuels crude. Hydrocarbons from oil a2levellevelrevision, chemistry. The combustion of hydrocarbon fuels releases energy 1 mark. Gcse chemistry what is the cracking of hydrocarbons. Difference between fractional distillation and cracking. Crude oil is a major source of hydrocarbons that is used to produce fuels. A hydrocarbon is a molecule that is made out of only hydrogen atoms and carbon atoms. Cracking is the name for a thermal decomposition processes. Please comment if you have any questions, and subscribe if you. We then pass the vapor over a hot catalyst, to speed up the reaction.
Cracking produces smaller hydrocarbons, smaller hydrocarbons have greater demand, they are easier to burn, and also cracking produces more reactive alkenes. The fractional distillation of crude oil produces alkanes. Common igcse chemistry exam questions with answers igcse. Gcse chemistry revision organic chemistry crude oil. See all crude oil, cracking and hydrocarbons resources. More lessons for igcse chemistry math worksheets a series of free igcse chemistry lessons cambridge igcse chemistry. Some of the large hydrocarbons the heavier fractions are broken down into more useful smaller hydrocarbons lighter fractions by a process known as cracking. Organic chemistry now forms a substantial part of the gcse specifications. Gcse chemistry 6 cracking hydrocarbons no rude comments please. The chemistry of cracking results in the formation. Industrial processes such as cracking and reforming use these fractions to make hydrocarbons, which are in short supply. The complete combustion of a hydrocarbon produces and.
Alternatively, we can mix the hydrocarbon vapor with very hot steam. Gcse chemistry science cracking hydrocarbons revision. The purpose of cracking is to produce high demand hydrocarbons. The rate of catalyst greatly depends upon the factors such as the presence of catalyst and temperature. The carbon atoms form a chain and the hydrogen atoms are bonded to the carbon chain. Hydrocarbons and crude oil gcse chemistry combined. By heating them with steam to a very high temperature of by. Take a look at our interactive learning flashcards about chemistry 5 cracking hydrocarbons gcse core, or create your own flashcards using our free cloud based flashcard maker. Gcse chemistry revision covering cracking and its products, hydrocarbons, catalyst, thermal decomposition, alkanes, single covalent bonds, alkenes, double covalent bonds, and cracking paraffin. Revise and summarise the key information for unit 7. Chemistry revision notes on the topic cracking hydrocarbons.
Fractional distillation and cracking are two such methods. Long alkane decane catalyst aluminium oxide heat shorter alkane octane and short alkene ethene labeling cracking gcse grade d describe the cracking process gcse grade b 8. Balance the equation for the complete combustion of this hydrocarbon. You tend to get molecules containing benzene rings and short hydrocarbons.
Cracking cracking is the breaking down of an unsaturated hydrocarbon into smaller hydrocarbons. By heating them with steam to a very high temperature or by. Organic chemistry from the combined science aqa gcse chemistry specification. First, crack the vapour of liquid paraffin by passing it over a heated catalyst to produce and collect a mixture of gaseous shortchain hydrocarbons. Revision homework cracking hydrocarbons the production of some products of fractional distillation of crude oil, such as naphtha, fuel oil and bitumen, exceeds demand. All that we need to do is heat longchain hydrocarbons, so that they turn into vapor.
Includes what cracking is and why it is useful, conditions for thermal and catalytic cracking, testing for alkenes and completing cracking equations. They react because sio 2 is acidic while cao is basic. Includes a couple of videos summarising the process cracking, and testing for alkenes. Please remember to leave feedback, for updates and promotions you can also follow me here. I print the starter as as handout sheet so they only have to complete the cloze exercise without writing everything. High octane starter to inject pace which is easily adapted for other lessons.
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