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. The defining characteristic of a homologous series is a repeating unit. Qualitative organic functional group tests in various homologous series. Some examples of functional groups in homologous series are alcohols oh, carboxylic acids cooh, aldehydes coh, ketones co, and amines n. Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or.
A homologous series is a family of compounds which have a general formula and have similar physical and chemical properties because they have the same. Jun 22, 2018 mathematical tables are super interesting. 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. How are alkanes, alkenes, and alkynes homologous series since. The priority order of functional groups in iupac nomenclature is based on a relative scale where all functional groups are arranged in the decreasing order of preference. Homologous series is a series of compounds with similar chemical properties and same functional group differing from the successive member by ch 2. What is a homologous series write the formula of functional.
Homologous series and functional groups ck12 foundation. Organic functional groups and homologous series flashcards. Sep 12, 2015 ib chemistry on homologous series and functional groups of organic molecules slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Organic functional groups and homologous series youtube. Structurallysimilar molecules within a series with the same functional group but different numbers of some repeated groups such as ch2. Organic compounds also have functional groups, which define the basic properties of the compound. Homologous series of alkanes, alkenes and alkynes with. For example, the alkane group contains the ch2 repeating unit. Consider structures of first five members of the series. Organic functional groups homologous series explained why.
Functional group this is an carbon atom or group of carbon atoms attached to an organic compund which determines the chemical properties. The nature of the functional groups should not be changed. A functional group is a class of organic compounds that have a function in common. A homologous series is a family of compounds which have a general formula and have similar physical and chemical properties because they have the same functional group of atoms i. Functional groups and homologous series question 1. Homologous series are referenced frequently in organic chemistry, where compounds can differ by the length of their carbon chain. 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. Structurallysimilar molecules within a series with the same functional group but different numbers of some repeated groups such as ch 2. A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula. Thus, a functional group is an atom or group of atoms which determine the chemical behavior of an organic compound. If the functional group is changed, isomerism also changes. The members of this series are called homologue and differ from each other by the number of ch2 units in the main carbon chain. They only differ in the number of methylene ch 2 groups. Difference between position isomerism and metamerism definition.
A summary of homologous series, functional group names and. This means that the compounds are identical with the exception of the number of ch2 units in the compound. Functional groups and homologous series earj ib chemistry. A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. As nouns the difference between ketone and benzophenone is that ketone is organic chemistry a homologous series of organic molecules whose functional group is an oxygen atom joined to a carbon atomby a double bondin a carbonhydrogen based molecule while benzophenone is. Homologous series, any of numerous groups of chemical compounds in each of which the difference between successive members is a simple structural unit. When organic compounds containing same functional group are arranged in series on the basis of their increasing molecular weight, having the difference of ch2. 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. A series of compounds having similar structural formulae, same functional group and hence similar chemical properties are called homologous series of compounds. Whats the difference between functional group and homologous.
Homologous seriesfunctional groups and isomerism, chemistry tutorial. A homologous series is a series of organic compounds that differ by a ch2 group within a functional group. Priority order of functional groups in iupac nomenclature. 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. If you continue browsing the site, you agree to the use of cookies on this website.
Describe the concept of homologous series as a family of similar compounds with similar properties due to the presence of the same functional group. Class functional groupname suffix examples formula. A functional group is an atom of a group of atoms which determines the characteristic properties of a particular compound. When a group is considered as principle functional group, it is indicated by suffix and when it acts as side chain, it is indicated by prefix. Homologous series meaning in the cambridge english. The alkanes, alkenes and cycloalkanes are examples of homologous series. A homologous series is a series of organic compounds which belong to the same family i. 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.
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. Physical properties change in a homologous series but chemical properties remain almost the same because the functional group does not change. Natures chemistry homologous series national 5 chemistry. The individual members of a homologous series are known as homologous and the process is known as homology. Jan 30, 2018 in organic chemistry, a functional group is a specific arrangement of atoms that confers specific chemical properties to the rest of the molecule. Mar 16, 2009 homologous series this are groups of organic compounds with same general formula and same function group with similar chemical properties. Feb 24, 2014 functional group functional group is a group of atoms tied together which will take part in a chemical reaction therefore determine the chemical properties of the series. 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.
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. Ib chemistry on homologous series and functional groups of organic molecules. Homologous seriesfunctional groups and isomerism, chemistry. However, the functional group finds out the properties of a homologous series. Notes on functional group and homologous series grade 11. Functional groups and homologous series sneak peek on. It covers structural and geometrical cistrans isomerism, but is does not cover optical isomerism. Feb 06, 2019 each functional group has its own distinctive properties c c h h h h h o h c c h h h h h c o h h c h h h o h these molecules have similar properties due to the presence of the oh group of atoms. 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. One of the features of a homologous series is that each and every member of a series includes at least one functional group.
Chapterwise dvds available for 11th and 12th chemistry with ncert book solutions. The functional group present in the following molecules are encircled. Match the functional group to the homologous series or compound class learn with flashcards, games, and more for free. Classification,homologous series and functional group. When an atom or group of atoms bonded to a carbon atom in the chain or ring of an organic. Reflect on previous knowledge of organic chemistry understand the term homologous series conduct the fractional distillation of crude oil understand and use the variety of different types of formula used in organic chemistry. A homologous series is a group of organic compounds which belong to the same family i.
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. Nov 16, 2017 there are some other conditions as well. This topic covers the simple types of isomerism encountered during most as level courses. Functional groups and homologous series question 2. Qualitative analysis tests for identifying organic functional. Describe the concept of homologous series as a family of. Members of the same homologous series have the same chemical properties because of the presence of a common functional group in all the molecules of the series. What is the difference between functional group and. Homologous series of alkanes, alkenes and alkynes with examples. Following are the characteristics of a homologous series. This increase in size causes the vanderwaals forces to grow, thus bonding the molecules to each other more strongly. We call this functional group a alcohol we can use the term homologous series to describe families of organic compounds with the same functional. This series of molecules is called homologous series.
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. The members of a homologous series have similar chemical properties. Difference between position isomerism and metamerism. No matter what size a molecule is, a functional group participates in chemical reactions in a predictable manner. Moving down a homologous series, the sizes of the compounds grow larger and larger. Functional groups and homologous series question 3. Drawing organic molecules, homologous series and isomers.
Ib chemistry on homologous series and functional groups of. A functional group is a specific group of atoms within a structure such as oh, cooh, nh2, co, hco, cn, these functional groups give rise to different properties within the molecule. They tend to all act the same in a chemical reaction. Common functional groups and their families of compound. For example, the oh group, when attached to a saturated carbon, makes the parent molecule an alcoho. Homologous series in organic chemistry are groups of molecules that have the same basic structure, including the same functional group. Carbon chains of varying length have been observed in organic compounds having the same general formula. This thus strengthens the attraction between the molecules and causes the boiling points to become higher. For example, the compounds given below belong to the alcohol. A few carbon compounds also exhibit a similar pattern. General formula, functional group and properties of alkanes. May 26, 2011 a homologous series is a series of organic compounds with similar formula and properties, properties are dependent on the functional group attached.
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