Members have the almost same chemical properties due to same functional group. Alkenes are more reactive than alkanes and react with bromine water, turning it from. A homologous series is a group or family of organic compounds that has certain characteristics. Describe the general characteristics of an homologous series. They show a steady change in physical properties from one member to the next. State any four characteristics of a homologous series.
In first year organic chemistry, the first ten names of the homologous series are usually all that need to be memorized. A homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group. Most of the homologous series are abundant in organic chemistry, but it is not unique only to organic chemistry. Deltastep is a social initiative by graduates of iimahmedabad, iimbangalore, iitkharagpur, isikolkata, columbia university usa, ntu singapore and other leading institutes. Aug 20, 2018 what is the homologous series of hydrocarbons what do you mean by homologous series. Homologous seriesfunctional groups and isomerism, chemistry tutorial. Characteristics of a homologous series k12 education. The carbon atoms have a unique property to combine with other carbon atoms repeatedly. Also each member of the series will be having an increase in mass no. Jul 27, 2015 deltastep is a social initiative by graduates of iimahmedabad, iimbangalore, iitkharagpur, isikolkata, columbia university usa, ntu singapore and other leading institutes. Categorisation relies on similarities between and within structures, giving rise to the concept of homologous series. The general characteristics of a homologous series are.
Homologous series homologous series characteristics. Wmpjan11chem1 12 do not write outside the box 12 6 octane is the eighth member of the alkane homologous series. Carbon chains of varying length have been observed in organic compounds having the same general formula. Homologous series grade 11 science notes reference notes. The difference between two consecutive members in their composition is ch 2 unit. 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 homopolymer such as amylose. Homologous series is a series of compounds with similar chemical properties and same functional group differing from the successive member by ch 2.
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. Lahvanya raoov moved describe the general characteristics of an. Alkanes, alkenes, alcohols, carboxylic acids and esters belong to different homologous series. Each member differs from successive member by ch 2. The characteristics of a homologous series is the study of the compounds of carbon in organic chemistry. Homologous series cie igcse chemistry revision notes. Homologous series are referenced frequently in organic chemistry, where compounds can differ by the length of their carbon chain.
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. Present general information about the definition, characteristics and structure of homologous including additional information not found in the original video lesson include at least 2 facts not. A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. Homologous series are not unique to organic chemistry. A homologous series is a family of hydrocarbons with similar chemical properties who share the same general formula. The physical and chemical properties of the series will show a continuous gradation. Alkenes are more reactive than alkanes and react with bromine water, turning it from orange to colourless the general formula for the homologous series of alkenes is cnh2n alkenes are hydrocarbons with a double carboncarbon bond. A series of organic compounds that have similar structural features but differ from adjacent members by ch 2 group is referred to as homologous series. Natures chemistry hydrocarbons and homologous series. The functional group of alcohols is the hydroxyl group i. Homologous series homologous series characteristics chemistry 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. Alkanes form a homologous series and so do alkenes.
In chemistry spm, students were introduced with five homologous series. Alkane, alkene, alcohol, carboxylic acids and esters. A series of organic compounds that have similar structural features but differ. All the members of a series can be represented by same general formula. The simplest series of compounds in organic chemistry is the alkanes. Difference in molecular mass of two consecutive members of the series is 14 unit i.
Describe characteristics of homologous series qs study. Jun 10, 2018 there will be a gradation in the physical and chemical properties. Such organic compounds that vary from one another by a repeating unit and have the same. Two adjacent members of homologous series differ by ch2 online chemistry tutorial iit, cbse chemistry, icse chemistry, engineering and medical chemistry entrance exams, chemistry viva, chemistry job interviews.
What are the characteristics of homologous series answers. It is atom or group of atoms or reactive part of compound which largely determines the chemical properties of compound, e. For example, the compounds given below belong to the alcohol family. Such series are most common among organic compounds, the structural difference being a methylene group. The table below shows the first four alcohols in the alcohol homologous series. The first four members of the homologous series of alkenes are ethene, propene, butene and pentene. It describes what are called a homologous series, examples of these series, and properties of some of selected homologous series in detail. Homologous series, any of numerous groups of chemical compounds in each of which the difference between successive members is a simple. Jan 10, 20 the characteristics of a homologous series is the study of the compounds of carbon in organic chemistry. Homologous series are referenced frequently in organic chemistry, where compounds can.
Homologous series are families of organic compounds. 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. A homologue also spelled as homolog is a compound belonging to a series of compounds differing from each other by a repeating unit, such as a methylene bridge. A group of organic compounds containing same functional group which can be represented by the same general formula and which have similar trends in their properties are called a homologous series. Oct 15, 2019 characteristics of a homologous series are. Homologous series is defined as a systematic order of organic compounds having same. All members of a series contain the same functional group i. They differ in formula from one member to the next by one ch2 unit. Difference in molecular mass of two consecutive members of the series is 14. All the members of a homologous series have same chemical properties due to. 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 characteristics of homologous series. 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 ch2. T he numerous organic compounds can be grouped into a comparatively small number of series or families of compounds known as homologous series.
Nov 01, 2019 homologous series khan academy, homologous series in hindi, homologous series class 11, homologous series igcse, homologous series in urdu, homologous series in organic chemistry, homologous. The functional group of aldehyde is aldehydic group i. Due to the presence of the same functional group, compounds within the same homologous series have similar chemical properties. The number of carbons continuously bonded together is an important structural feature and is described using the homologous series. For example, methane, ethane, and propane are part of a homologous series. We shall study this series to illustrate what a homologous series means. For example, methane, ethane, propane, butane, etc. Significance and properties of the homologous series. It is a series of compounds which are derived from same general formula, having same functional group, similar chemical properties and show gradation in physical properties.
They are named by replacing the final e in the corresponding alkane by ol. Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or. The sheer scale of organic chemistry means that it is important to categorise compounds with similarities in order to make sense of the vast number of organic compounds possible. Write any 4 characteristic features of homologous series of organic compounds. Order in homologous series photograph shows the first members of various homologous series. Natures chemistry homologous series national 5 chemistry. The table shows some information about three members of a homologous series. 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. The following is one of the chemistry spm 2009 questions related to homologous series. This is a series or family of organic compounds that have similar features and chemical properties due to them having the same functional group.
In organic chemistry, a homologous series is a series of compounds with the same functional group. In chemistry, homology is the appearance of homologues. Dec 04, 2018 the first four members of the homologous series of alkenes are ethene, propene, butene and pentene. Lahvanya raoov moved describe the general characteristics of an homologous series lower. What are the general characteristics of a homologous 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. Tutorials for chemistry learning functional groups and homologous series functional groups.
This video is created by more videos and free notes are available at. Oct 10, 2014 this article gives an explanation for the homologous series and their characteristics. Each member of homologous series is called homolog. Jan 10, 2018 characteristics of a homologous series. Based on the table, state and explain five characteristics of a homologous series. A homologous series in organic chemistry is a group of organic compounds compounds that contain carbon c atoms that diverge from each other by one methylene ch 2 group.
A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula. Write any 4 characteristic features of homologous series of. The members of the homologous series have same functional group. The characteristics of a homologous series is outlined below. Significance and properties of the homologous series gulpmatrix. Naming branched chain alkanes homologous series national. 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 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. Homologous series organic compounds are grouped into different homologous series. The optical band gaps were determined by uvvis and fluorescence spectroscopy in solution. Titanium, vanadium, and molybdenum oxides all form homologous series e. What is the homologous series of hydrocarbons what do you mean by homologous 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. Ch 3 oh methyl alcohol methanol ch 3 ch 2 ch 2 oh propyl alcohol.
A series of a organic compound each containing a characteristic functional group and the successive members differ by from each other in molecular formula by ch2methylene group is called homologous series. What are the physical and chemical properties of homologous. Currentvoltage characteristics of a homologous series of. The alkanes, alkenes and cycloalkanes are examples of homologous series. Alcohols in the homologous series can be regarded as alkanes in which one hydrogen atom is replaced by a hydroxyl group. Characteristics of homologous series carbon compound youtube. Common functional groups and their families of compound. The organisation of organic compounds into the various different homologous series makes the study of organic chemistry more systematic, orderly and effective.
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