State 5 properties of a homologous series names have same endings. A series of organic compounds in which hydrogen in a carbon chain is replaced by the same functional group, is called homologous series. Homologous series are referenced frequently in organic chemistry, where compounds can differ by the length of their carbon chain. Functional groups and homologous series revision question 12. Functional group definition of functional group by the free. The difference between two consecutive members in their composition is ch 2 unit. In chemistry, a homologous series is a group of compounds that share the same basic chemical makeup, but differ in the number of iterations of a certain aspect of their structure. Significance and properties of the homologous series gulpmatrix. Homologous series in organic chemistry are groups of molecules that have the same basic structure, including the same functional group. Homologous series of alkanes, alkenes and alkynes with.
Hybridization in carbon atoms a functional group is an atom, a radical group of atoms or a bond common to a homologous series, and which determines the main chemical properties of the series. In the field of organic chemistry, a homologous series is a series of compounds with the same functional group and similar chemical properties in which the members of the series can be branched or unbranched this can be the length of a carbon chain, for example in the straightchained alkanes paraffins, or it could be the number of monomers in a. At the end of the lesson the students should be able to. Functional groups and homologous series question 2. General formula, functional group and properties of alkanes. A homologous series is a series of compounds with the same general formula, usually varying by a single parameter such as the length of a carbon chain. Functional groups are the substituent atoms or group of atoms that attach to a molecule and enable them to participate in specific chemical reactions.
Homologous series groups of related having the same chemical functions and the same type of structure organic compounds that differ from one another only by one or more methylene ch2 groups. The alkanes, alkenes and cycloalkanes are examples of homologous series. The defining characteristic of a homologous series is a repeating unit. A homologous series is a group of organic chemical compounds, usually listed in order of increasing size, that have a similar structure and hence, also similar properties and whose structures differ only by the number of c h 2 units in the main carbon chain. The ch 2 group is nonpolar hydrophobic and this increases the percentage of the molecule that is unattractive to water. The main functional groups for as chemistry are shown below. An homologous series is a group of compounds with similar structural features that can be represented by a general.
Notes on homologous series grade 10 science carbon and. A homologous series is a group of organic chemical compounds, usually listed in order of increasing size, that have a similar structure and hence also similar properties and whose structures differ only by the number of ch2 units in the main carbon chain. But if the first definition is to be considered then how can alkanes, alkenes or alkynes be considered homologous series since there is no functional group attached to any of these, as opposed to, e. In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and shows a gradation in physical properties as a result of increase in molecular size. Functional groups and homologous series question 3. The functional groups within a molecule need to be identified when naming.
How are alkanes, alkenes, and alkynes homologous series. An atom or group of atoms, such as a carboxyl group, in an organic compound that defines the structure of a. Because the functional group is the same for each molecule in a homologous series, the homologues have similar reactivities. Thus, a functional group is defined as an atom or group of atoms linked with. The difference between each member of an homologous series is one ch 2 unit. An homologous series is a group of compounds with similar structural features that can be represented by a general formula whose members differ by one ch 2 unit you can think of an homologous series as a family or group of compounds, whose chemical behaviour is very similar and whose physical properties show trends when ascending the members of the group in terms of. Information and translations of homologous series in the most comprehensive dictionary definitions resource on the web. Thus, a functional group is an atom or group of atoms which determine the chemical behavior of an. Common functional groups and their families of compound. A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula. The functional group is an atom or group of atoms, that is responsible for the chemical behaviour of that organic compound. All compounds having the same carbon framework skeleton and the same functional group in. Typically the presence of an amine functional group is deduced by a combination of techniques, including mass spectrometry as well as nmr and ir spectroscopies. In the field of organic chemistry, a homologous series is a series of compounds with the same functional group and similar chemical properties in which the members of the series can be branched or unbranched.
The members of this series are called homologue and differ from each other by the number of ch 2 units in the main carbon chain. Notes on homologous series grade 10 science carbon. Definition taken from lecture supplement, first edition by steven hardinger. Organic compounds also have functional groups, which define the basic properties of the compound. All the compounds within a homologous series have the same general molecular formula and the same functional group carboncarbon, hydroxyl, carboxyl, ester, etc. Each members differs from the next by a common structural unit. Introduction the word homologous series and functional groups describe a few of the umbrella principles that assist in the understanding of organic compounds in spite of their large number. A homologous series is defined as a series of organic compounds having similar functional group and similar properties, in which the successive members or compounds differ by ch2. Thus, the presence of the functional group or groups determines the chemical, properties of a homologous series.
Homologous series is defined as a systematic order of organic compounds having same functional group that can be represented by same general formula and prepared by same method. In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and shows a gradation in physical properties as a result of increase in molecular size and mass see relative molecular mass. Any two adjacent homologues differ by ch 2 in their molecular formulae all the compounds of a homologous series show similar chemical properties. Name functional groups and classify organic compounds according to their functional groups. Mar 16, 2009 functional group a funtional group is an atom or a group of atoms that defines the structure or the chemical properties of a particular family of organic compounds. For example, the compounds given below belong to the alcohol. When studying reactions of a homologous series, the alkyl group is relatively unimportant it is the functional group that reacts. Define homologous series science carbon and its compounds. A homologous series is a series of organic compounds which belong to the same family i. A homologous series is a series of carbon compounds that have different number of carbon atoms but contain the same functional group. The individual members of a homologous series are known as homologous and the process is known as homology. Homologous series and functional groups ck12 foundation. In chemistry, a homologous series is a series of compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group.
In the field of organic chemistry, a homologous series is a series of compounds with the same functional group and similar chemical properties in which the. All the members of the same series cant be represented by the same general formula. A homologous series is a group of chemicals which have similar chemical properties and can be. The members of the homologous series consists of same general formula such as alkanes have general formula c n h. No matter what size a molecule is, a functional group participates in chemical reactions in a predictable manner. Natures chemistry homologous series national 5 chemistry. The series which consists of similar structures and similar chemical properties in which the successive compounds differs by a ch 2 group is termed as homologous series. For example, methane, ethane, propane, butane, etc.
An homologous series is a group of compounds with similar structural features that can be represented by a general formula whose members differ by one ch 2 unit. Compounds within a homologous series typically have a fixed set of functional groups that gives them similar chemical and physical properties. Homologous series is a series of compounds with similar chemical properties and same functional group differing from the successive member by ch 2. The individual members of a homologous series are known as homologous and. An homologous series is a family of compounds that all contain the same functional group s and differ in successive members by one ch2 unit. A series of compounds having a same functional group but a different number of carbon atoms is known as homologous series. A homologous series homos is greek for the same as can be defined as the group of compounds in which the various members have similar structural features and similar chemical properties and the successive members differ in their molecular formula by one methylene ch 2 group. A functional group is an atom of a group of atoms which determines the characteristic properties of a particular compound. Consider structures of first five members of the series. Homologous series of alkanes, alkenes and alkynes with examples. In their infrared spectrum primary amines exhibit two nh bands, whereas secondary amines exhibit only one. The two characteristics of homologous series are as follows. Define homologous series series of compounds of the same family, with the same general formula, which differ from each other by a common structural unit, and differ by a ch2 group in successive members.
Any two adjacent homologues differ by ch 2 in their molecular formulae. Organic compounds belonging to the main class can be divided into different families, known as homologous series, on the basis of similarity in structure and chemical properties. A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. They only differ in the number of methylene ch 2 groups. Organic compounds consequently tend to be less soluble as an homologous series is ascended. This means that the compounds are identical with the exception of the number of ch2 units in the compound. More example sentences because of these regularities, the members of each group are known as a homologous series. Homologous series is defined as a systematic order of organic compounds having same functional group that can be represented by same general formula and. Functional groups and homologous series question 1. Structurallysimilar molecules within a series with the same functional group but different numbers of some repeated groups such as ch2. Functional groups and homologous series functional groups.
A homologous series in organic chemistry is a group of organic compounds compounds that contain c atoms that differ from each other by one methylene ch 2 group. For a more enjoyable learning experience, we recommend that you study the mobilefriendly republished version of this course. All of the compounds in a homologous series have the. Notes on functional group and homologous series grade 11. Functional group definition of functional group by the. Organic functional groups homologous series explained why.
When an atom or group of atoms bonded to a carbon atom in the chain or ring of an organic compound, shown some characteristic properties of their own, they are termed as a functional group. Homologous series article about homologous series by the. Define homologous series of organic compounds list its two. Naming branched chain alkanes homologous series national. Define homologous series and explain general characteristics of its members. A homologous series is a group of organic compounds, which has the same functional group, but two successive members differ by ch 2 group. Significance and properties of the homologous series. How are alkanes, alkenes, and alkynes homologous series since. Homologous series homologous series characteristics. A homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group. Organic functional groups and homologous series youtube. Thus, a functional group is an atom or group of atoms which determine the chemical behavior of an organic compound. If you continue to study chemistry to a level, you will meet more functional groups.
Previous topic previous slide next slide next topic. Definition of cyclic hydrocarbon and cyclic alkane are given. Carbon chains of varying length have been observed in organic compounds having the same general formula. Oct 29, 20 in chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and. Functional groups and homologous series revision question 9. For example, the alkane group contains the ch2 repeating unit. The functional group gives the molecule its properties, regardless of what molecule contains it. Homologous seriesfunctional groups and isomerism, chemistry tutorial. Homologous definition, having the same or a similar relation. Functional groups include hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl. Functional groups definition a functional group or moiety is a specific group of atoms within a molecule that is responsible for characteristic chemical reactions of that molecule. Examples of functional groups, homologous series, general formula, displayed formula.
When organic compounds containing same functional group are arranged in series on the basis of their increasing molecular weight, having the difference of ch 2 methylene group in between two consecutive compounds, such series is called homologous series. A functional group is an atom, a radical group of atoms or a bond common to a homologous series, and which determines the main chemical properties of the series. Jan 11, 2016 compounds within a homologous series typically have a fixed set of functional groups that gives them similar chemical and physical properties. In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due to the presence of the same functional group, and.
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