What is a homologous series? Write any four characteristics of a homologous series. Write the molecular formula and structural formula of the third and fifth members of the homologous series of alcohols.

Q: What is a homologous series? Write any four characteristics of a homologous series. Write the molecular formula and structural formula of the third and fifth members of the homologous series of alcohols.

Definition of Homologous Series\nA homologous series is a family of organic compounds having similar chemical properties, all members of which contain the same functional group and can be represented by a general formula, in which each successive member differs from the previous one by a $-CH2-$ group (or a molecular mass difference of 14u). Characteristics of a Homologous Series General Formula: All members of a homologous series can be represented by a single general chemical formula. For example, alcohols are represented by $Cn{H}{2n+1}OH$. Difference in Molecular Formula: Any two adjacent (successive) members of the series differ by a $-CH2-$ group in their molecular formulas. Difference in Molecular Mass: The difference in molecular mass between any two successive members is 14 atomic mass units (u) (since carbon has mass 12u and two hydrogens have mass 2u). Chemical Properties: All members of a homologous series show similar chemical properties because they contain the same functional group. For example, all alcohols react with sodium to evolve hydrogen gas. Gradation in Physical Properties: The physical properties of the members, such as melting point, boiling point, and solubility, show a gradual gradation (increase or decrease) with an increase in molecular mass due to an increase in intermolecular forces. Members of the Homologous Series of Alcohols\nThe general formula for alcohols is $Cn{H}{2n+1}OH$. Third Member of Alcohol Series ($n = 3$): Substituting $n = 3$ in $Cn{H}{2n+1}OH$ gives: $C3{H}{2(3)+1}OH \Rightarrow C3H7OH$ (Propanol) Molecular Formula: $C3H8O$ (or $C3H7OH$) Structural Formula: $CH3 - CH2 - CH2 - OH$ Fifth Member of Alcohol Series ($n = 5$): Substituting $n = 5$ in $Cn{H}{2n+1}OH$ gives: $C5{H}{2(5)+1}OH \Rightarrow C5H{11}OH$ (Pentanol) Molecular Formula: $C5H{12}O$ (or $C5H{11}OH$) Structural Formula: $CH3 - CH2 - CH2 - CH2 - CH2 - OH$

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Definition of Homologous Series
A homologous series is a family of organic compounds having similar chemical properties, all members of which contain the same functional group and can be represented by a general formula, in which each successive member differs from the previous one by a $-CH2-$ group (or a molecular mass difference of 14u). Characteristics of a Homologous Series General Formula: All members of a homologous series can be represented by a single general chemical formula. For example, alcohols are represented by $Cn{H}{2n+1}OH$. Difference in Molecular Formula: Any two adjacent (successive) members of the series differ by a $-CH2-$ group in their molecular formulas. Difference in Molecular Mass: The difference in molecular mass between any two successive members is 14 atomic mass units (u) (since carbon has mass 12u and two hydrogens have mass 2u). Chemical Properties: All members of a homologous series show similar chemical properties because they contain the same functional group. For example, all alcohols react with sodium to evolve hydrogen gas. Gradation in Physical Properties: The physical properties of the members, such as melting point, boiling point, and solubility, show a gradual gradation (increase or decrease) with an increase in molecular mass due to an increase in intermolecular forces. Members of the Homologous Series of Alcohols
The general formula for alcohols is $Cn{H}{2n+1}OH$. Third Member of Alcohol Series ($n = 3$): Substituting $n = 3$ in $Cn{H}{2n+1}OH$ gives: $C3{H}{2(3)+1}OH \Rightarrow C3H7OH$ (Propanol) Molecular Formula: $C3H8O$ (or $C3H7OH$) Structural Formula: $CH3 - CH2 - CH2 - OH$ Fifth Member of Alcohol Series ($n = 5$): Substituting $n = 5$ in $Cn{H}{2n+1}OH$ gives: $C5{H}{2(5)+1}OH \Rightarrow C5H{11}OH$ (Pentanol) Molecular Formula: $C5H{12}O$ (or $C5H{11}OH$) Structural Formula: $CH3 - CH2 - CH2 - CH2 - CH2 - OH$

MP Board · Class 10 · Science · Carbon and its CompoundsWhat is a homologous series? Write any four characteristics of a homologous series. Write the molecular formula and structural formula of the third and fifth members of the homologous series of alcohols.

Characteristics of a Homologous Series

Members of the Homologous Series of Alcohols\nThe general formula for alcohols is $C_n{H}_{2n+1}OH$.