Alkanes are also used as fuels and the environmental consequences of this use are considered in this section. Alkanes are less dense than water and swim on top of water 2. After watching the covalent bonds video you should have sufficient knowledge to understand about how alkanes and. To find a word on this page, press f3 on your keyboard and enter text into the box.
Preparations include the dehydration of alcohols, the dehydrohalogenation of alkyl halides, and. Alkenes are hydrocarbons that contain one or more double bonds, while alkynes contain one or more triple bonds. The process of adding hydrogen across a double bond is sometimes referred to as hydrogenation. Some further addition reactions of ethene are shown.
Some of the worksheets displayed are, gcse 9 1 chemistry, work for organic chemistry, chemistry 30 work, gas laws work, aqa ocr edexcel gcse science, alkanes and alkenes work. Alkanes and alkenes are both families of hydrocarbons. Alkenes alkenes are unsaturated hydrocarbons, meaning they contain a double covalent bond co. As the number of carbon atoms in a straight chain alkane increases, the boiling points rise in a uniform and predictable manner. Energetics and hydrocarbons chemistry bibliographies. Longer alkanes have structural isomers different arrangements of the same atoms so the formula is the same. New aqa 2016 gcse chemistry organic lesson 6, 7 and 8 alkenes chemistry. Alkenes have physical properties low boiling points, insoluble in water quite similar to those of their corresponding alkanes. Isomers of an alkane are two or more alkanes with the same molecular formula but a different structure. The longer the alkane the more ways there are to rearrange the atoms differently. Alkanes are useful as fuels and alkenes are used to make chemicals such as.
This holds true for the two compound groups, alkanes and alkenes. Table 2 shows the boiling points of some alkanes and alkenes. Which of the following is are true of the process of polymerisation. Combustion of fossil fuels including alkanes results in the release of carbon dioxide into the atmosphere carbon dioxide. Addition reactions of alkenes are useful in organic synthesis. Whereas the names of alkanes end with the suffix ane, alkenes end with the suffix ene. Crude oil has been described as a complex mixture of hydrocarbons. Determination of an equilibrium constant using spectroscopy. In organic chemistry, we will learn about the reactions chemists use to synthesize crazy carbon based structures, as well as the analytical methods to characterize them. Alkenes, also known as olefins, are organic compounds that consist of carbon and hydrogen atoms with one or more carboncarbon double bonds in their chemical structure. This video explain the properties of alkenes, its general formula and how to name and draw alkene molecules for students preparing for gcse and o. Saturated and unsaturated hydrocarbons, structure and uses. Physical properties the simplest alkenes are gases at room temperature, then liquids, finally solids, due to increased molecular mass.
Alkene and alkyne compounds are named by identifying the longest carbon chain that contains both carbons of the. Powerpoint going through key points and activities for teaching alkenes and alkanes. Reactions of alkanes and alkenes organic compounds ocr gateway gcse chemistry single science revision ocr gateway bbc bitesize, n. Further addition reactions of ethene addition reactions of alkenes are useful in organic synthesis. We look at the general formula for alkenes and then look at how alkenes are unsaturated hydrocarbons. Included is a differentiated worksheet to summarise the two groups. The naming conventions for these compounds are similar to those for alkanes. Alkenes alkanes, alkenes and plastics gcse chemistry. The book is now out of print, but if you are interested, you may be able to obtain a secondhand copy from.
A small difference in the molecule changes the name and can drastically change the reactivity of the compound. Might be able to condense to two lessons, but i feel the addition reactions need to be focused on as will be a new concept for all students. Halogenation is the replacement of one or more hydrogens in an organic compound with halogen atoms. Discover the differences between alkanes and alkenes, and learn about the properties and uses of polymers with bbc bitesize gcse chemistry wjec. Petrol and other fuels are produced from it using fractional distillation. Alkanes contain only ch and cc bonds, which are relatively strong and difficult to break. Once you find your worksheet, click on popout icon or print icon to worksheet to print or. Thermal cracking takes place at high pressure and high temperature and produces a high percentage of alkenes mechanism not required. Testing for alkenes alkanes, alkenes and plastics gcse. If you are simply interested in a generalpurpose introduction to chemistry for 14 16 yearolds, you might be better looking at my edexcel igcse chemistry book. In addition, the type of bonding in organic compounds is almost always covalent. It can be used to aid learning of the topic or as a revision resource.
Written by teachers for the edexcel igcse chemistry course. This makes them relatively unreactive, apart from their reaction with oxygen in the air, which is called combustion, or burning. Alkanes alkanes, alkenes and plastics gcse chemistry. Alkenes basics and reactions of including addition reactions.
Carbon dioxide itself is not poisonous and is found naturally in the atmosphere. Discover the differences between alkanes and alkenes with bbc bitesize gcse chemistry. New aqa 2016 gcse chemistry organic lesson 6, 7 and 8. Therefore, it needs to be separated into its different products called fractions. Gcse chemistry the periodic table index search gcse physics.
Original post by mattlogan does anybody have any good revision techniques on how to revise alkanesalkenes for chemistry, cheers what do you intend by a revision technique. This means that their carbon atoms are joined to each other by single bonds. Name the test used to determine where an alkene is present. It is the process of breaking down a large molecule. Alkanes are useful as fuels and alkenes are used to make chemicals such as plastic. If you know how to name alkanes, adding alkene nomenclature to your repertoire is a fairly straightforward task. Alkenes are more reactive than alkanes due to the presence of the double bond. It involves heat, great pressure and the presence of a catalyst. Reactions of alkanes and alkenes organic compounds ocr gateway gcse chemistry single science revision ocr gateway bbc bitesize. We will also think about how those reactions are occurring on a molecular level with reaction mechanisms. While alkanes and alkenes are both hydrocarbons, the primary difference is that alkanes are saturated molecules, containing only single covalent bonds. However, due to the enormous amount of hydrocarbons burnt over the years the level of carbon dioxide has risen to dangerous levels.
Gcse chemistry index page what is an alkane revision. Showing top 8 worksheets in the category chemistry gcse. Crude oil and hydrocarbons crude oil, hydrocarbons and. Research uses of alkenes to help with homework homework.
Introduction of a halogen into a molecule chlorination, bromination general reaction. B halogenation halogenation a substitution reaction. Alkanes are the main constituent of crude oil, which is an important raw material for the chemical industry. Combustion alkanes and alkenes gcse chemistry single. Pentane only refers to a straight chain of 5 carbon atoms singly bonded to hydrogen atoms. Alkanes and alkenes organic chemistry wyzant resources. Organic chemistry is the study of carbon compounds, so the study of organic chemistry is important because all living things are based on carbon compounds. Alkanes and alkenes a handy introduction to alkanes and alkenes, their similarities, and differences. Cracking is used to convert long alkanes into shorter, more useful hydrocarbons. Preparations alkenes are generally prepared through. The similar electronegativities of carbon and hydrogen give molecules which are nonpolar. Choose from 500 different sets of exam organic chemistry test alkanes flashcards on quizlet. Hydrocarbons 365 unit after studying this unit, you will be able to name hydrocarbons according to iupac system of nomenclature.
272 336 446 1110 912 300 1183 384 502 1101 426 1294 383 547 753 462 844 864 1008 201 1147 1316 787 1301 1109 56 1076 833 330 977 1327 1175 355 1347