Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or alkanes. Give the formula and name of the member with two carbon atoms. The dna binding characteristics of a series of homologous 2,6disubstituted anthraquinone threading intercalators bearing one to four ethylene glycol units in. Such series are most common among organic compounds, the structural difference being a methylene group, as in the paraffin hydrocarbons, or. Jul 27, 2015 deltastep is a social initiative by graduates of iimahmedabad, iimbangalore, iitkharagpur, isikolkata, columbia university usa, ntu singapore and other leading institutes. 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. Each member of the series differs from the preceding one by the addition of a ch2 group and by 14 a. Which element is composed of atoms that can form more than one covalent bond with one another. Nature of element all the members of series have same type of elements. Homologous series chemistry, class 11, organic chemistry. They also carry genes that determine individual traits that can be inherited through reproduction. What is the total number of valence electrons in a carbon in the ground state.
The difference between two consecutive members in their composition is ch 2 unit. Binding of a homologous series of anthraquinones to dna. Hole doping and superconductivity characteristics of the s. Thus the molecular mass of each member differs by 14 atomic mass units.
They only differ in the number of methylene ch 2 groups. Homologous series, any of numerous groups of chemical compounds in each of which the difference between successive members is a simple structural unit. A homologous series is a group of chemicals which have similar chemical properties and can be represented by a general formula. This lesson covers the definition of a homologous series of molecules in. The first four straightchain alkanes are shown below. Every member in the homologous series can be represented by a common formula. Common characteristics of homologous series explained by augustine emeka. Ways to identify homologous series are discussed as well as the chemical and physical properties of homologous series. Describe the properties of alkanes exemplified by methane as being generally unreactive, except in terms of burning. In chemistry, a homologous series is a series of organic compounds with a similar general formula, possessing similar chemical properties due.
Nov 15, 2017 common characteristics of homologous series explained by augustine emeka. The table shows some information about three members of a homologous series. The first four alkanes in the homologous series retain their original names. 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. H c c h 2 c compounds in the same homologous series have the same general formula. State the type of compound present, given a chemical name ending in ane, ene and ol, or a molecular structure. Compounds within a homologous series typically have a fixed set of functional groups that gives them similar chemical and physical properties. Chemistry assignment help, characteristics of homologous series, characteristics of homologous series i all the members of a series can be presented by the general formula. Organic chemistry, homologous series, cracking hydrocarbons.
The number of carbon atoms may be considered as the size of the. Write the molecular formula of two consecutive members of homologous series of aldehydes. In that series, successive members differ in mass by an extra methylene bridge ch 2 unit inserted in the chain. In a homologous series there is a gradual increase in boiling point as the number of carbon atoms increases. The alkanes, alkenes and cycloalkanes are examples of homologous series. 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. The following is one of the chemistry spm 2009 questions related to homologous series. Dec 15, 20 a homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group. For detailed treatments of the properties, states, and behaviour of bulk matter.
Translocation mutation between non homologous chromosomes is not to be confused with crossover between homologous chromosomes or regions of chromosomes. Each homologous series has its own general formula. In an alkane, each carbon atom is sp 3hybridized with 4 sigma bonds either cc or ch, and each hydrogen atom is joined to one of the carbon atoms in a ch bond. The alkanes form an homologous series of hydrocarbons. The longest series of linked carbon atoms in a molecule is known as its carbon skeleton or carbon backbone. 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. 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. A homologous series is defined as a family or group of structurally.
Oct 15, 2019 characteristics of a homologous series are. For example, the boiling points of the alkanes increase down the series, so that the first four members are gases at room temperature and standard pressure. A homologous series is a series of carbon compounds that have different numbers of carbon atoms but contain the same functional group. A pair of homologous chromosomes contains chromosomes of similar length, gene position, and centromere location. The physical properties of the members change gradually as the number of carbon atoms per molecule increases. All members of a homologous series share the general formula.
For example, methane, ethane, propane, butane, etc. The general characteristics of a homologous series are. All the members of a homologous series have same structural formula. Natures chemistry hydrocarbons and homologous series. Homologous series in organic chemistry are groups of molecules that have the same basic structure, including the same functional group. The physical propertieslike solubility, melting point, boiling point, state of. Homologous series is defined as a systematic order of organic compounds having. The number of carbons continuously bonded together is an important structural feature and is described using the homologous series. Homologous series of alkanes, alkenes and alkynes with. The functional group of alcohols is the hydroxyl group i. In first year organic chemistry, the first ten names of the homologous series are usually all that need to be memorized. For example, you could look at boiling points of h2o, h2s, and h2se and then explain the difference with a discussion of. 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. Apr 14, 2015 there are many different types of hydrocarbons which are organised into homologous series in order to categorise them with other compounds with similar characteristics.
Start studying an introduction to organic chemistry learn vocabulary, terms, and more with flashcards, games, and other study tools. 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. A series of compounds with similar chemical properties, in which members differ from one another by the possession of an additional ch2 group, is called a homologous series. Hydrocarbons the alkanes and alkenes are examples of homologous series. Homologous series grade 11 science notes reference notes. The successive members vary from each other by a ch 2 unit. Deletion, the loss of genetic material, and duplication, the. 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. Octane is the eighth member of the alkane homologous series. State any four characteristics of a homologous series. Within a given homologous series the chemical properties of the compounds are. Based on the table, state and explain five characteristics of a homologous series. For categorya phases, a widely adopted practice,, has been to discuss both the chemical oxygen content, hole doping, etc.
The formula of methane is ch4 and the formula of ethane is c2 h6. Characteristics of homologous series carbon compound youtube. Significance and properties of the homologous series. The 4 single bonds of a carbon atom are directed in space toward the corners of a regular tetrahedron in which group could the hydrocarbons all belong to the same homologous series. After these the names are formed by adding the ending ane to the greek word for the number of carbon atoms in the molecule. Wmpjan11chem1 12 do not write outside the box 12 6 octane is the eighth member of the alkane homologous series.
Natures chemistry homologous series national 5 chemistry. Chromosomes are important molecules because they contain dna and genetic instructions for the direction of all cell activity. Homologous series are referenced frequently in organic chemistry, where compounds can differ by the length of their carbon chain. The 4 characteristics which change with increasing molecular mass in a homologous series are as follows. Deltastep is a social initiative by graduates of iimahmedabad, iimbangalore, iitkharagpur, isikolkata, columbia university usa, ntu singapore and other leading institutes. Molecular formula molecular formula of different members of a homologous series differs from previous and next member by ch 2. State two other characteristics of an homologous series.
Homologous series of alkanes, alkenes and alkynes with examples. Characteristics of homologous series 1 all compounds in the series are composed of same elements and contain the same functional group. 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. 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. Cch 2 ch 3 name ethyne butyne 2 b complete the dotandcross diagram to show the electron arrangement in a molecule of ethyne, hc. Each homologous series must have the following four characteristics. 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. State which part of these compounds determines their i physical and ii chemical properties. Common characteristics of homologous series youtube. Predict and explain the trends in boiling points of members of a homologous series. Jan 25, 2020 a translocation mutation is a type of mutation in which a piece of one chromosome breaks off and is joined to another chromosome. 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. For example, methane, ethane, and propane are part of a homologous series.
A homologous series is a family of hydrocarbons with similar chemical properties who share the same general formula. Download the byjus app and get in touch with our mentors for any further queries. Homologous series homologous series characteristics. Ethene, propene and but2ene are members of the alkene homologous series. Significance and properties of the homologous series gulpmatrix.