Identify these compounds and write an equation for the reaction. To describe what cracking is and its economic benefits. These notes on cracking alkanes to make alkenes for plastics and other products from cracking like petrol and diesel fuels are designed to meet the highest standards of knowledge and understanding required for studentspupils doing gcse chemistry, igcse chemistry, o level chemistry. Depending on the end product, the oils can go directly into fuel blending, or they can be routed through further cracking reactions or other. Cracking produces the smaller hydrocarbons which make up petrol gasoline. Simply put, hydrocarbon cracking is the process of breaking a longchain of. This is expensive as the hydrocarbons are subject to high temperature and pressure. Pupils can share their ideas in pairs, then as a class, before being introduced to the process of cracking. Cracking chemistry is a text book i wrote to address the everincreasing need for a suitable textbook to go along with my teachings of chemistry as a subject at school as well as to fill the void of an easily understandable,well written. To help you check your progress and understanding, the answers for the end of chapter questions in international a level chemistry for oxford international aqa examinations are available here. Heat a known mass of two metals to produce their oxides and. For example, a higher hydrocarbon c 1 0 h 2 2 splits according to the reaction. Cracking is a type of chemical reaction in which hydrocarbon molecules.
Semih eser, professor of energy and geoenvironmental engineering, college of earth and mineral sciences, penn state. Model the industrial process of cracking larger hydrocarbons to produce smaller. There are many websites, but few deal with this topic at the 14 18 chemistry teaching and learning level most are either far too technical or too elementary. Covers thermal and catalytic cracking, ppt file, application questions, answers and an assessed homework activity with mark scheme. A cracking practical can be carried out in a school lab quite easily by using a broken pottery as a catalyst. A level chemistry ocr textbook answers edexcel asa level chemistry student book 1 answers kerboodle ocr as chemistry breadth mon 20th may unofficial markscheme. In an exam, you could just as well be asked to make up your own. Cracking edexcel igcse chemistry notes save my exams. Cracking hydrocarbons in liquid paraffin with a catalyst resource. Cracking chemistry has been listed as a level 5 vital article in an unknown topic. Also check out our other helpful revision resources for o level chemistry 5070. You can find instructions for this experiment at resourceres00000681crackinghydrocarbons liquid paraffin. Experimental chemistry particulate nature of matter acids bases salts properties and uses of ammonia sulphuric acid stoichiometry and the mole concept introduction to organic chemistry alkanes alkenes alcohols. Petrol gasoline contains a mixture of hydrocarbons, with 5 to 10 carbon atoms, but the products of fractional distillation do not completely suit the desired mixture for a.
By the end of this lesson ks5 students should be able to. Cracking chemstuff chemstuff mr bankss chemistry site. Cracking of the unbranched compound e, c6h14, produced the saturated compound f and an unsaturated compound g mr 42. Cracking allows large hydrocarbon molecules to be broken down into smaller, more useful hydrocarbon molecules. This statement is about the use of cracking to make smaller and more useful.
Cracking of petroleum yields light oils corresponding to gasoline, middlerange oils used in diesel fuel, residual heavy oils, a solid carbonaceous product known as coke, and such gases as methane, ethane, ethylene, propane, propylene, and butylene. Thermal cracking breaks cc bonds by homolytic fission forming free radicals. C 16 h 34 is an alkane which can be used as the starting chemical in cracking. Fractions containing large hydrocarbon molecules are heated to vaporise them. This is a thermal decomposition reaction known as cracking. Cracking and alkenes gcse chemistry single science revision. Explore over 400 exciting practical experiments for your classroom. As level chemistry nomenclature and isomerism 46 terms. Catalytic cracking breaks cc bonds by heterolytic fission forming ions. Graded with a video link and mark schemes for everything. The purpose of cracking is to produce high demand hydrocarbons. Cracking of the unbranched compound e, c6h14, produced the.
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. Cracking is the breaking down of an unsaturated hydrocarbon into smaller hydrocarbons. Mechanism for thermal cracking a level chemistry the. Hydrocarbons from oil a2levellevelrevision, chemistry. Year 12 lesson graded outstanding to teach cracking.
The zeolites used in catalytic cracking are chosen to give high percentages of hydrocarbons with between 5 and 10 carbon atoms particularly useful for petrol gasoline. Reforming, in chemistry, processing technique by which the molecular structure of a hydrocarbon is rearranged to alter its properties. Chemistry catalytic cracking help related articles a level chemistry help lastminute a level chemistry revision. Thermal reforming alters the properties of lowgrade naphthas by converting the molecules into those of higher octane number by exposing the materials. This video shows an overview about cracking paraffin. Aqa alevel chemistry fractional distillation and cracking. Free o level chemistry revision notes that will help you in revising for your exams. To compare and evaluate the conditions for and the products of thermal and catalytic cracking. Catalytic cracking processes heavy longchain fractions obtained in larger quantities than required. Engaging video tutorials for the new ocr, aqa and edexcel spec.
In this video well look at the process of industrial cracking. Cracking hydrocarbons in liquid paraffin with a catalyst. The process is frequently applied to lowquality gasoline stocks to improve their combustion characteristics. That is so that you can mark your answers more easily. Wikipedia a good overview of industrial processes for hydrocarbon cracking.
A brief description of the difference between thermal and catalytic cracking of alkanes. 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. This website and its content is subject to our terms and conditions. In chemistry, it is a process of breaking down large alkane into simpler alkenes and alkanes. Cracking is the process whereby long and medium chain hydrocarbons are heated and break apart giving short chain alkanes, alkenes and hydrogen. O level chemistry revision notes archives teachifyme. A structured lesson including starter activity, afl work tasks on cracking of alkanes. As chemistry aqa cracking alkanes teaching resources. This is a dangerous scientific experiment and must not be attempted without skilled supervision. The molecules are broken up in a random way which produce a mixture of alkanes and alkenes. Thermal cracking takes place at high pressure and high temperature and produces a high percentage of alkenes mechanism not required. Unlock the full a level chemistry course at created by ella buluwela, chemistry expert at snaprevise. Cracking is the breakdown of a large alkane into smaller, more useful alkenes. Cracking is the process of breaking longer chained alkanes down into smaller alkanes and alkenes, sometimes for polymer manufacture, and sometimes to improve octane number.
Learn vocabulary, terms, and more with flashcards, games, and other study tools. The process of breaking higher hydrocarbons with high boiling points into a variety of lower hydrocarbons that are more volatile low boiling, is called cracking or pyrolysis. Aqa a level chemistry modification of alkanes by cracking. Similarly cracking of hydrocarbons includes breaking down of a complex long chain of hydrocarbons into smaller ones.
Chemguide a discussion of the cracking of hydrocarbons for alevel chemistry students and teachers. Cracking is the process of breaking up the long chain hydrocarbons which are in high supply but low demand, into short chain hydrocarbons that are in low supply but high demand. Introduction to cracking a problem of supply and demand and other products. Alkanes alevel chemistry ocr, aqa, edexcel youtube. In petroleum refining, this process is used in the production of petrol, diesel, and gasoline. This video runs through alkanes, alkenes and haloalkanes followed by fractional distillation and cracking. Cracking is the starting point for the manufacture of many organics. It also produces high proportions of branched alkanes and aromatic hydrocarbons like benzene. Aqa a level chemistry flashcards decks in this class 88. Resources and inspiration for practical work and demonstrations.
Cracking oil fraction hydrocarbons to produce more useful products. Doc browns gcseigcseo level ks4 sciencechemistry revision notes oil. This forms a mixture of straightchain alkanes and alkenes mainly ethene with a. Cracking and alkenes crude oil, hydrocarbons and alkanes aqa. Cracking and alkenes crude oil, hydrocarbons and alkanes. This site contains notes, exercises, exam questions and tests to cover the new aqa a level chemistry course. Sections also exist to cover the legacy ocr a chemistry and the west african senior secondary chemistry specifications. Oxford aqa international a level chemistry answers. Practical chemistry activities are accompanied by our standard health and safety guidance. The mechanism is free radical and it is difficult to control the composition of the products, which are mixtures of short chain alkanes and alkenes.