For saturated carbon chains alkanes the numbering system for the base carbon chain is determined by the positions of the substituents. Classes of hydrocarbons molecules that are made up of carbon and hydrogen 1. Conformation of alkanes and cycloalkanes because of free rotation around cc single bonds atoms or groups attached to the bond carbons can be in various spatial relationships to one another. Section 3 stereochemistry of alkanes and cycloalkanes. The proton nmr spectra of alkanes and cycloalkanes are characteristic. Conformational isomers stereochemistry concerned with the 3d aspects of molecules. Hydrocarbons the simplest class of organic compounds a. Jul 30, 2018 alkanes, hydrocarbons, class 11 the acyclic saturated hydrocarbons are called paraffins since they are relatively unreactive towards most of the reagents such as acids, bases oxidizing and reducing agents. Alkanes and cycloalkanes section 2 of organic chemistry notes is 18 pages in length page 21 through page 218 and covers all youll need to know about the following lecturebook topics. Alkane and cycloalkane nomenclature i organic chemistry. In organic chemistry, the cycloalkanes also called naphthenes, but distinct from naphthalene are the monocyclic saturated hydrocarbons. Winner of the standing ovation award for best powerpoint templates from presentations magazine. The cyclohexane ring is free of angle strain and torsional strain the conformation has alternating atoms in a common plane. Chem 1060 lecture 009 chemical properties of alkanes and cycloalkanes duration.
Cycloaliphatics or cycloalkanes contain the alkane or alkyl fragment as part of a carbon cycle. Naming cycloalkanes according to iupac rules duration. Alkanes are organic compounds that consist of singlebonded carbon and hydrogen atoms. First, note that cycloalkanes can also appear as substituent groups as well as the main molecule. Alkanes are the simplest and least reactive hydrocarbon species containing only carbons and hydrogens. We often refer to alkanes as aliphatic hydrocarbons, because the physi cal properties of the higher members of this class resemble those of the long carbonchain. Draw newman projections of alkanes in staggered and eclipsed conformations, and arrange the order of stability for these conformations conformational isomers. Cycloalkanes are alkanes with carbon atoms attached in the form of a closed ring. For example, if you have one carbon in your molecule you plug one into your formula there, and you would get c1, and you would get 1 times 2 plus 2, which is of course 4, so ch4. Learn organic chemistry exam 2 alkanes cycloalkanes with free interactive flashcards.
Draw the line bond structures of following types of hydrocarbons using four carbon atoms. These different spatial arrangements are known as different conformations. This text is published under creative commons licensing, for referencing and adaptation, please click. Cycloalkanes cycloalkane formula cycloalkanes properties. Alkanes are the simplest and least reactive hydrocarbon species containing only. The aromatic hydrocarbons are unstable hydrocarbons which contain one or more benzene rings, to which hydrogen molecules are attached with the formula c n h 2n. Alkanes and cycloalkanes free download as powerpoint presentation. Alkanes formula, definition, structure, properties.
What follows applies equally to alkanes and cycloalkanes. Lowry theory of acids and bases lewis theory of acids and bases. Hydrocarbons of this kind are classified as alkanes or cycloalkanes. Alkanes and cycloalkanes structure, nomenclature and conformations.
Rating the combustion of alkanes is a complicated reaction probably involving free radicals. Alkanes and cycloalkanes 1992 patais chemistry of functional. The two methyl groups are not fixed in a single position but are free to rotate. A free powerpoint ppt presentation displayed as a flash slide show on id. Kerosine, boiling point 180 to 230, contains hydrocarbons from c, to c. Cycloalkanes have one or more rings of carbon atoms. Most reactions of organic compounds take place at or adjacent to a functional group. We do not observe perfectly free rotation there is a barrier to rotation, and some conformers are more stable than others. What is the general formula for a noncyclic alkane. Cycloalkanes reactivity of alkanes properties of alkanes alkenes and alkynes nomenclature isomers.
Cyclic saturated hydrocarbons with a general formula of cnh2n. The iupac names, molecular formulas, and skeleton structures of the first ten cycloalkanes are given in table 4. Alkane names, formulas, properties memorize sections. Bsc or bachelor of science is basically a 3year undergraduate program designed for individuals who want a career in the field of science bsc 1st year consists of two semesters, i. These saturated hydrocarbons are said to have their boiling points ranging between 10 20 k. Since alkanes are the major components of petroleum. Aliphatic alkanes are linear or branched structures as shown in the example above. Alkane names, formulas, properties memorize sections 3. Lower members of cyclo alkanes are usually reported by simple geometrical drawing as etc. Well be learning about different aspects of molecular structure, including common functional groups and conformations.
Although a cycloalkane has two fewer hydrogens than the equivalent. Alkane and cycloalkane nomenclature i organic chemistry khan academy. In this context, saturated means that each carbon has the maximum number of hydrogens bonded to it. These carbon skeletons show great diversity in the ways that c atoms bond to. Alkanes, cycloalkanes, and functional groups khan academy. Cycloalkanes only contain carbonhydrogen bonds and carboncarbon single bonds. Alkanes all have the general molecular formula of cnh2n plus 2, where n is the number of carbons that are in your molecule. Alkanes react with halogens in a socalled free radical halogenation reaction. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. Write the structures of constitutional or structural isomers of alkanes. Cycloalkanes are hydrocarbons with a ringlike structure. If a noncyclic alkane contains 15 carbon atoms, how many hydrogen atoms does it contain. They tend to consume with a dingy fire, and many have a sweet fragrance. Alkanes are virtually insoluble in water, but dissolve in organic solvents.
Course outcome ability to explain the relationship between the structure, physical and chemical properties of the different bonds and functional groups in organic compounds co2 course learning outcome the student should be able to. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from. Understanding alkanes and cycloalkanes universalclass. Free radicals are the reactive species that participate in the reaction, which usually leads to a mixture of products. This post includes download links for bsc 1st year chemistry notes pdf. The removal of one h atom from cycloalkanes give rise to cycloalkyl radicals e. The physical properties of alkenes are much like those of the alkanes. The simplest examples of this class consist of a single, unsubstituted carbon ring, and these form a homologous series similar to the unbranched alkanes. This is a very important topic in chemistry and biochemistry. Alkanes and alkyl groups can be subclassified as aliphatic acyclic or cycloaliphatic based on their general structure. Simple cycloalkanes are named by adding the prefix cycloto the name of the acyclic alkane having the same number of carbons. Properties of alkenes and alkynes no rotation around double and triple bonds similar to alkanes bp and mp isomerism cis and trans. Choose from 500 different sets of organic chemistry exam 2 alkanes cycloalkanes flashcards on quizlet.
The branched alkanes make better gasoline than their con tinuouschain isomers because they give less knock in highcompression gasoline engines. Alkanes and alkane isomers alkanes and cycloalkanes alkane isomers the molecular formula of an. In order to establish a baseline of behavior against which these reactions may be ranked, we need to investigate the reactivity of compounds lacking any functional groups. Carbon can bond in different ways c h h h h c h h h h ch 4. In other words, a cycloalkane consists only of hydrogen and carbon atoms arranged in a structure containing a single ring possibly with side chains, and all of the carboncarbon bonds are single. The system is similar to that of alkanes but with a few subtleties. Substituent names in alphabetical order and numbers are added prefixed to the base name of the compound. The slightly higher boiling points for the cycloalkanes are presumably because the molecules can get closer together because the ring structure makes them tidier and less wriggly. The properties of organic molecules depend on the structure, and knowing the names of organic compounds allow us to communicate with other chemists. An atom or groups of atoms that substitute for a hydrogen atom in an organic compound, giving the compound unique chemical properties and determining its reactivity. Apr 14, 2012 alkane and cycloalkane nomenclature i organic chemistry khan academy.
Alkane and cycloalkane nomenclature i video khan academy. Structures and reactions find, read and cite all the. The hydrogen atoms of the alkane are progressively replaced by halogen atoms. Alkanes and cycloalkanes 11 million organic compounds which are classified into families according to structure and reactivity functional group fg. The chlorine free radicals are very reactive and remove an h from the methane leaving a methyl free radical the methyl free radical reacts with a cl2 molecule to produce the main product and another cl free radical all propagation steps have a free radical in the reactants and in the products. The various physical and chemical properties of cycloalkanes are given belowthe first four classes of cycloalkanes are said to be in gaseous state at the room temperature. The reaction is highly exothermic, and can lead to an explosion. Alkanes, hydrocarbons, class 11 the acyclic saturated hydrocarbons are called paraffins since they are relatively unreactive towards most of the reagents such as acids, bases oxidizing and reducing agents. Cycloalkanes have similar properties to alkanes but have higher breaking points 4. The first 12 nalkanes are listed in the handout essential nomenclature. Janice gorzynski smith university of hawaii chapter 4 alkanes.
265 1322 737 159 31 1265 671 391 873 225 177 441 374 386 1368 559 654 911 274 52 251 699 518 946 1093 629 80 1461 953 1377 190 1167 226 1330