A series of compounds where each consecutive member differs from one particular unit is called a homologous series. Difference in molecular mass of two consecutive members of the series is 14 unit i. What are the general characteristics of a homologous series. During sexual reproduction, one chromosome in each homologous pair is donated from the mother and the other from the father. For example, methane, ethane, and propane are part of a homologous series. Due to the presence of the same functional group, compounds within the same homologous series have similar chemical properties. Homologous series a homologous series is a group of compounds with similar characteristics and the same general formula. 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.
Homologous series meaning in the cambridge english. 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. They show a steady change in physical properties from one member to the next. 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. In the field of organic chemistry, a homologous series is a sequence of compounds with the same functional group and similar chemical properties in which the. Members of the homologous series are called homologs. Homologous series is a series of compounds with similar chemical properties and same functional group differing from the successive member by ch 2. In first year organic chemistry, the first ten names of the homologous series are usually all that need to be memorized. Ch3och3, c2h5och3, c3h7och3 are the members of homologous series called ethers. For example, you could look at boiling points of h2o, h2s, and h2se and then explain the difference with a discussion of.
For example, methane, ethane, propane, butane, etc. A homologous series is a family of hydrocarbons with similar chemical properties who share the same general formula. General characteristics of members of homologous series definition members of the series can be represented by a general formula. Homologous series cie igcse chemistry revision notes. Porous texture characteristics of a homologous series of basecatalyzed silica aerogels. All the members of a series can be represented by same general formula. Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or. Also each member of the series will be having an increase in mass no. The functional group of aldehyde is aldehydic group i.
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. In a karyotype, there are 22 pairs of autosomes or nonsex chromosomes and one pair of sex chromosomes. Homologous series definition in the cambridge english. Ethanol, propanol and butanol undergo oxidatoin produce carboxylic acids. The members of a homologous series can be represented by same general formula. A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula.
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. The characteristics of a homologous series is the study of the compounds of carbon in organic chemistry. Successive members differ from each other by c h 2. Homologous series definition 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. Homologous series chemistry, class 11, organic chemistry. Oct 10, 2014 this article elaborates some of these characteristics with examples. Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or alkanes. Such a family of compounds is known as a homologous. Homologous structures are discussed in evolutionary biology and refer to body parts in modern organisms that show evidence for descent with modification from a common ancestor. Homologous series are referenced frequently in organic chemistry, where compounds can. This means that the compounds are identical with the exception of the number of ch2 units in the compound. They also carry genes that determine individual traits that can be inherited through reproduction.
Physical properties change regularly with increasing number of carbon atoms. The organisation of organic compounds into the various different homologous series makes the study of organic chemistry more systematic, orderly and effective. Mar 20, 2019 characteristics of a homologous series. A homologous series is a group or family of organic compounds that has certain characteristics. Homologous series chemistry britannica encyclopedia britannica.
Features include a general formula and neighbouring members differing by ch2, with similar chemical properties and with a gradation in physical properties. 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. The members of a series have same functional group. Alkanes, alkenes and alkynes are some examples for this series. Order in homologous series photograph shows the first members of various homologous series. In organic chemistry, a homologous series is a series of compounds with the same functional group.
Describe the general characteristics of a homologous series. Jan 25, 2020 every chromosome pair represents a set of homologous chromosomes. All members of a series contain the same functional group i. For example, the alkane group contains the ch2 repeating unit. Describe characteristics of homologous series qs study. Detailed revision notes on the topic homologous series. All members of a homologous series exhibit some common characteristics.
Chemicals in the same homologous series will show a gradual variation in one property eg. Homologous series examples, answers, activities, experiment. Characteristics of a homologous series general formula. Two consecutive members of a homologous series differs each. Homologous series meaning in the cambridge english dictionary. The compounds in a homologous series should have 1 similar chemical formulas 2 similar chemical properties 3 physical properties that show a gradual change or trend based on the differences in their formulas for example, you could look at boiling points of h2o, h2s, and h2se and then explain the difference with a discussion of intermolecular.
The table shows some information about three members of a homologous series. A hydrocarbon homologous series is a series of hydrocarbons which. The same thing can be observed in case of alkenes in which the first member is ethene and the successive members are c 3 h 6, c 4 h. Homologous series have the following common characteristics. For example in ch 4 and c 2 h 6, the difference is ch 2 unit and the difference between c 2 h 6 and c 3 h 8 is also ch 2 unit. All the members of a series can be represented by the same general formula. Homologous series homologous series characteristics. Homologous series, any of numerous groups of chemical compounds in each of which the difference between successive members is a simple structural unit.
Homologous series of alkanes, alkenes and alkynes with. The successive members differ in their molecular formula by ch2 group, they differ in molecular weight by 14 units. The carbon atoms have a unique property to combine with other carbon atoms repeatedly. Nov 01, 2019 homologous series and its characteristics, homologous series a level chemistry, homologous series and examples, homologous series and their functional group, homologous series of aldehyde. The difference between two consecutive members in their composition is ch 2 unit.
Choose from 352 different sets of homologous series flashcards on quizlet. Significance and properties of the homologous series. Such organic compounds that vary from one another by a repeating unit and have the same. The following is one of the chemistry spm 2009 questions related to homologous series. 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. Jan 10, 20 the characteristics of a homologous series is the study of the compounds of carbon in organic chemistry. Carbon chains of varying length have been observed in organic compounds having the same general formula. In that series, successive members differ in mass by an extra methylene bridge ch 2 unit inserted in the chain. First two members of alkena series and il third and fourth member of aldehyds ssries. Characteristics of homologous series carbon compound. What are the characteristics of homologous series answers. Significance and properties of the homologous series gulpmatrix.
The alcohols which only contain one hydroxyl group attached to a saturated carbon form a homologous series. A homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group. 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. 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. The alkanes, alkenes and cycloalkanes are examples of homologous series.
State any four characteristics of a homologous series. Members of the homologous series can be prepared using the same method. The difference in molecular mass of two consecutive members. Homologous series are families of organic compounds. In the field of organic chemistry, a homologous series is a sequence of compounds with the same functional group and similar chemical properties in which the members of the series can be branched or unbranched. The defining characteristic of a homologous series is a repeating unit.
Difference in molecular mass of two consecutive members of the series is 14. Introduction to chemistry class 11 unacademy jee iit jee chemistry paaras sir unacademy jee 1,920 watching live now. Natures chemistry homologous series national 5 chemistry. They differ in formula from one member to the next by one ch2 unit. The homologous series of straightchained alkanes begins methane ch 4, ethane c 2 h 6, propane c 3 h 8, butane c 4 h 10, and pentane c 5 h 12. Alkanes, alkenes, alcohols, carboxylic acids and esters belong to different homologous series.
The successive members vary from each other by a ch 2 unit. The physical and chemical properties of the series will show a continuous gradation. Learn homologous series with free interactive flashcards. Some examples of homologous series are shown in the following table. Members have similar chemical properties because they have same functional group. Oct 15, 2019 characteristics of a homologous series are. Aug 20, 2018 a homologous series is a group or family of organic compounds that has certain characteristics. The functional group of alcohols is the hydroxyl group i. Alcohols are hydrocarbon compounds containing one or more hydroxyl group o h attached to a saturated carbon atom. The number of carbons continuously bonded together is an important structural feature and is described using the homologous series.
Properties of homologous series definition, examples, diagrams. 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. What is the molecular formula of the 2nd and 3rd members. Characteristics of homologous series 1 all compounds in the series are composed of same elements and contain the same functional group. Properties of homologous series definition, examples. A pair of homologous chromosomes contains chromosomes of similar length, gene position, and centromere location. The general characteristics of a homologous series are.
What are the physical and chemical properties of homologous. Each member of homologous series is called homolog. Two consecutive members of a homologous series differs each other in their composition by ch 2. Homologous series of alkanes, alkenes and alkynes with examples. The characteristics of a homologous series is outlined below. Differ by ch 2 in molecular formulae from neighbouring compounds. What are the characteristics of a homologous series. Characteristics of homologous series carbon compound youtube.