Cracking hydrocarbon chains will be expected for all three exam boards which are. 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. Apparatus delivery tube and bung bunsen burner boiling tube containing mineral wool porous pot liquid paraffin clamp and stand. One of the byproducts of this thermal decomposition reaction is ethene. Journal of catalysis 10, 277289 1968 hydrocarbon cracking reactions on nickel j. Cracking is the name given to breaking up large hydrocarbon molecules into. A hydrocarbons are broken down 1 mark to produce smaller more useful molecules 1 mark. This is the first if six quizzes on that subject and it looks in particular at the hydrocarbons and alkanes which are found in crude oil. Please remember to leave feedback, for updates and promotions you can also follow me here.
This forms a mixture of straightchain alkanes and alkenes mainly ethene with a small proportion of branched and cyclic hydrocarbons. Chemistry hydrocarbons and fuels aqa in gcse science one topic studied is crude oil and other types of fuel. New91 aqa gcse chemistry c9 crude oil and fules kerboodle. One of the topics studied in the chemistry section of gcse science is hydrocarbons.
The names of these three states are shown in the boxes. A brief description of the difference between thermal and catalytic cracking of alkanes. In this video, we look at how cracking is used to convert longchain hydrocarbons into shorterchain hydrocarbons. For example, butane is an alkane with four carbon atoms. Liquid paraffin a mixture of alkanes of chain length c20 and greater is vaporised and passed over a hot pumice stone catalyst. Cracking takes place at high temperatures as the large molecules pass over a catalyst. Petroleum as a source of hydrocarbons by fractional distillation and cracking. The name given to hydrocarbons with single bonds only is. It only has simple ch bonds throughout its whole structure.
Thermal cracking gives mixtures of products containing high proportions of. Petroleum as a source of hydrocarbons by fractional. Dec 31, 2015 summary video on cracking for gcse chemistry. These alkenes are very reactive due to their double bonds and therefore can be used to make other substances. Catalytic cracking breaks cc bonds by heterolytic fission forming ions. Alkenes along with alkanes can be produced from cracking. A gaseous product is obtained which is flammable and which will. Cracking and alkenes crude oil, hydrocarbons and alkanes. Naming an organic compound by interprating the formula. Crude oil is a mixture of compounds called hydrocarbons which are separated in a fractionating column.
Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds alkenes. Ethene, for example can be used to make ethanol and polythene. Written by teachers for the edexcel igcse chemistry course. Best igcse organic chemistry notes complete breakdown. Some of the large hydrocarbons the heavier fractions are broken down into more useful smaller hydrocarbons lighter fractions by a process known as cracking. This is a gross oversimplification, and is written to satisfy the needs of one of the uk a level exam boards aqa.
Cracking oil and cracking gcse chemistry single science. Designed by expert teachers for the edexcel gcse 91 chemistry syllabus. Cracking and alkenes crude oil, hydrocarbons and alkanes aqa. The numbers 1, 2, 3 and 4 represent changes of state.
Gcse chemistry what is the cracking of hydrocarbons. Please comment if you have any questions, and subscribe if you. 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. Ethene c 2 h 4 is an example of a family of hydrocarbons called the alkenes. This is the second of six quizzes on that subject and it looks specifically at hydrocarbons the compounds of carbon and hydrogen in crude oils.
To aid your revision, have a go at this fun aqa syllabus a quiz and go over what you learned in year 10 and year 11. Crude oil is described as a fossil fuel but it is much more important than that as many plastics have crude oil as a raw material. Petrol and other fuels are produced from it using fractional distillation. Gcse fuel revision of hydrocarbon compounds in crude oil. The petrochemical industry, the industrial production of ethene activity 2. May 22, 2012 for double award you only need to know the haber process, single award people, you also need to know the contact process for the manufacture of sulphuric acid. Give the name of a catalyst used in industry to crack longchain hydrocarbons and state a temperature at which cracking is carried out. In all the following, students are required to apply or relate their understanding to a range of situations or scenarios. Hydrocarbon cracking reactions on nickel sciencedirect.
Apart from alkenes and alkanes what else is made during the process of cracking. This page contains the aqa gcse chemistry c9 hydrocarbons questions and kerboodle answers for revision and understanding hydrocarbons. Simply put, hydrocarbon cracking is the process of breaking a longchain of hydrocarbons into short ones. C 3 h 8 the following formula satisfies the general formula of alkane, and consists of 3 carbon atoms. Targeted towards aqa c1 topic 5 but suitable for edexcel and other exam boards too.
To find out the products formed when hydrocarbons burn, the apparatus. Subject contents for the 6 important sections discussed above for 0620 igcse chemistry past year papers. If the answer you have written is not right, change it. Past paper questions crude oil, fractional distillation. There is a much greater demand for shorter hydrocarbon than there is for the longer hydrocarbons. Galwey from the chemistry department, the queens university o belast, northern ireland received june 21, 1967. Have a go at this interactive aqa syllabus a quiz and revise what youve learned about their chemistry. Gcse chemistry products from oil medium demand questions questionsheet 14 some of the products of the distillation of crude oil are used as fuels. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Cracking is used to convert long alkanes into shorter, more useful hydrocarbons. Crude oil is a dark smelly liquid which is a mixture of many different. Many of the substances with longer molecules produced from the fractional distillation of crude oil are cracked.
Mar 24, 2019 this resource is a broken down practice exam question to help improve exam technique when answering exam questions on cracking hydrocarbons. C 3 h 7 oh the following is an alcohol as we can see a oh group is attached to it, with three. The best way to remember the information in this chapter is to get a pen and paper and write down your answers. The alkane c 14h 30 might split in a variety of different ways.
The name given to hydrocarbons with at least one double bond is. And be careful with your phrasing cracking produces alkenes and shorter chain alkanes. Cracking hydrocarbons edexcel gcse chemistry revision notes. Cracking is the breakdown of a large alkane into smaller, more useful alkenes. This video prepares students for gcse higher tier science.
Gcse chemistry revision organic chemistry crude oil. Give two examples of properties of hydrocarbons that are dependent upon the size of the hydrocarbon molecule. Compare the hydrocarbons in fractions d and f in terms of x boiling point x size of molecules x viscosity 3. This is a thermal decomposition reaction known as cracking. Crude oil hydrocarbons and alkanes aqa test questions.
To find out the products formed when hydrocarbons burn, the apparatus below is used. Cracking is the process whereby long and medium chain hydrocarbons are heated and break apart giving short chain alkanes, alkenes and hydrogen. These are the compounds of carbon and hydrogen found primarily in crude oil and used to make fuels. The rate of cracking and the end products are strongly dependent on the temperature and presence of catalysts. It does not have any functional group, hence alkanes are quite inert in nature. Cracking edexcel igcse chemistry notes save my exams.
The purpose of this process is to get the simpler molecules from the complex organized molecules. Hydrocarbons from oil a2levellevelrevision, chemistry. Long chain hydrocarbons can be broken into smaller hydrocarbons, by heating with a catalyst. Vladimir shukhov took the credit as the first person who invented and patented the cracking method in 1891. After the fractional distillation of crude oil there are too many large hydrocarbons and not enough small hydrocarbons to meet the publics demand. During the cracking process, hydrocarbons are first heated to vaporise them. The petrochemical industry, pressure and steam in ethene production activity 3. The name given to hydrocarbons with at least one triple bond is. Igcse chemistry past year papers 0620 download twins. Oldsetaqa gcse chemistry topic 610 paper 2 quizlet. To do well in gcse science, year 10 and year 11 students will need to know what hydrocarbons and alkenes are. Cracking is a form of thermal decomposition, which breaks long chain hydrocarbons, many of which are not very useful, into shorter molecules by heating them. What is the cracking of hydrocarbons after the fractional distillation of crude oil there are too many large hydrocarbons and not enough small hydrocarbons to meet the publics demand.
Thermal cracking heats the naphtha fraction with steam at a high temperature about 800c and high pressure. Cracking of ethane and propane to produce ethylene. Gcse triple chemistry revision topic 10 using resources questions and answers. Chemistry revision notes on the topic cracking hydrocarbons. Chemistry crude oil aqa one of the topics covered in gcse science is the chemistry of crude oil and other fuels. Catalytic cracking processes heavy longchain fractions obtained in larger quantities than required. Free gcse chemistry science cracking hydrocarbons practice exam question. Thermal cracking breaks cc bonds by homolytic fission forming free radicals. You need to know about alkanes, alkenes, crude oil and the process of cracking.
Alkane is the simplest of all the homologous series. Pressure and steam an interesting aspect of ethene production. Vapours will then pass over a hot catalyst of silica. Free gcse chemistry science cracking hydrocarbons practice. Cracking is used to make longchain hydrocarbon molecules into shorterchain. Cracking produces shortchain hydrocarbons called alkanes, like petrol and alkenes, like ethene and propene. Complete the sentences using the words in the boxes. This page also contains the link to the notes and video for the revision of this topic c9. Crude oil hydrocarbons and alkanes aqa test questions aqa. Learn about crude oil, hydrocarbons and alkanes with bitesize gcse chemistry aqa.
Are larger hydrocarbons more or less flammable than smaller hydrocarbons. Candidates should be able to make simple choices based upon the analysis and evaluation of information provided when. During combustion, the and in the fuels are oxidised. Give an example of a method by which cracking can be carried out. Facts about cracking hydrocarbons present the information about a process of cracking employed in the chemistry and petroleum geology. Stick with shorter as opposed to short because if you crack a larger alkane you could end up with an alkane as a product that you wouldnt normally describe as short. Learn the basics about the cracking of hydrocarbons and why it is done. Fractions containing large hydrocarbon molecules are heated at 600 700c to vaporise them.
Cracking is considered as a very important process for it can generate coke, gas oil and. Start studying oldsetaqa gcse chemistry topic 610 paper 2. Oldsetaqa gcse chemistry topic 610 paper 2 flashcards. Cracking oil fraction hydrocarbons to produce more useful products. Write equations for the cracking of c 14h 30 which lead to the. C 5 h 10 the following formula satisfies the general formula of alkene and consists of 5 carbon atoms. The simplest alkenes have the general formula c n h 2n. In petrochemistry, petroleum geology and organic chemistry, cracking is the process whereby complex organic molecules such as kerogens or longchain hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carboncarbon bonds in the precursors. In the petroleum industry, large hydrocarbons from the distillation of crude oil are often cracked to split them into smaller bits.
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