Homologous Series

Q.

What is homologous series? Explain with examples. What are the characteristics of homologous series? [5 MARKS]

Q. What is a homologous series and what are its characteristics? [5 MARKS]

Q.

The general formula for alcohol is

Q. The successive members of a homologous series differ by a mass of ______amu.

1. 14

Q. Question 25
Which of the following does not belong to the same homologous series?
(a) ${\text{CH}}_4$
(b) ${\text{C}}_2{\text{H}}_6$
(c) ${\text{C}}_3{\text{H}}_8$
(d) ${\text{C}}_4{\text{H}}_8$

Q. Which of the following belong to same homologous series:
C₃H₈, C₃H₆, C₄H₈, C₄H₆

Q. Give the names of the first four members of the homologous series of alkynes.

Q.

Name the simplest hydrocarbon.

Q.

Which of the following is an alkyne ?

1. C₆H₆

2. C₆H₁₂

3. C₆H₁₄

4. C₆H₁₀

Q.

What is the difference between two consecutive homologues :
(i) in terms of molecular mass?
(ii) in terms of number and kind of atoms per molecule?

Q.

The molecular formula of the third member of the homologous series of ketones is :
(a) $C_4{H}_{8}O$ (b) $C_3{H}_{6}O$ (c) $C_5{H}_{10}O$ (d) $C_6{H}_{12}O$

Q.

The molecular formula of a homologue of butane is :
(a) $C_4{H}_8$ (b) $C_3{H}_6$ (c) $C_4{H}_6$ (d) $C_3{H}_8$

Q. The structure of heptene has 12 hydrogen atoms.

1. True
2. False

Q.

Ethane, Ethene, Ethanoic acid, Ethyne, Ethanol

From the above, name
(a) The compound with –OH as the part of its structure,
(b) The compound with –COOH as the part of its structure.
(c) Homologue of homologous series with general formula $C_n{H}_{2n}$.

Q. The first member of homologous series of ketones is:

1. 
2. 
3. 
4. 

Q. What is the homologous series of alcohols, aldehyde, ketones, and carboxylic acid ?

Q. (a) What is a homologous series?
(b) What is the difference in the molecular formula of any two adjacent homogues:
(i) in terms of molecular mass,
(ii) in terms of number and kind of atoms per molecule? [3 MARKS]

Q.

What is the next higher homologue of methanol $\left(C{H}_{3}OH\right)$?

Q. Write the molecular formula of first two members of homologous series having functional group CI
(pls explain)

Q.

ASSERTION: n-Pentane and n-Hexane belong to a homologous series.

REASON: n-Pentane and n-Hexane belong to the same class of hydrocarbons and they differ by a - $C{H}_2$ - group.

1. ASSERTION is correct but REASON is incorrect

2. Both ASSERTION REASON are correct and REASON is the correct explanation for ASSERTION

3. Both ASSERTION REASON are correct but REASON is not the correct explanation for ASSERTION

4. Both ASSERTION REASON are incorrect.

Q.

(a) Define a homologous series. Give the name and structural formula of one homologue of the following :
$C{H}_{3}OH$
(b) Write the molecular formula of the third member of the homologous series of carbon compounds with general formula $C_n{H}_{2n+1}OH.$
(c) Name any two fossil fuels.

Q.

Assertion (A): Following are the members of a homologous series: ${\mathrm{CH}}_3\mathrm{OH},{\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH},{\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{OH}$

Reason (R): A series of compounds with same functional group but differing by $–{\mathrm{CH}}_2–$ unit is called a homologous series.

1. Both (A) and (R) are true and (R) is correct explanation of the assertion.

2. Both (A) and (R) are true but (R) is not the correct explanation of the assertion.

3. (A) is true but (R) is false.

4. (A) is false but (R) is true.

Q.

Classify the following as alkanes, alkenes, and alkynes.

$C{H}_4,C_2{H}_4,C_2{H}_2,C_2{H}_6,C_3{H}_4$

Q.

(a) What is a homologous series ? Explain with an example.
(b) State two characteristics of a homologous series.
(c) The molecular formula of an organic compound is $C_{18}{H}_{36}.$ Name its homologous series.
(d) Select the hydrocarbons which belong to the same homologous series. Give the name of each series.
$C{H}_4,C_2{H}_2,C_2{H}_4,C_2{H}_6,C_4{H}_{10},C_3{H}_4,C_3{H}_6$
(e) What is meant by 'heteroatom'? Give examples. Write the names and formulae of two organic compounds containing different heteroatoms.

Q. The next homologue of ethene in the homologous series of alkene is.

1. ethyne
2. propene
3. ethane

Q. The next homologue of ethene in the homologous series of alkene is.

1. ethyne
2. propene
3. ethane

Q.

Copy and complete the following table which realtes to three homologous series of hydrocarbons:

$\begin{array}{cccc}\text{General Formula}& C_n{H}_{2n}& C_n{H}_{2n-2}& C_n{H}_{2n+2}\\ \text{IUPAC name of the homologous series}& & & \\ \text{Characteristic bond type}& & & \text{Single bonds}\\ \text{IUPAC name of the first member of the series}& & & \\ \text{Type of reaction with chlorine.}& & \text{Addition}& \end{array}$

Q.

(a) Give the names and structural formulae of the next two higher homologues of methane.
(b) The molecular formula of a hydrocarbon is $C_{10}{H}_{18}.$ Name its homologous series.
(c) Select the hydrocarbons which are members of the same homologous series. Give the name of each series.
$C_5{H}_{10};C_3{H}_8;C_6{H}_{10};C_4{H}_{10};C_7{H}_{12};C_8{H}_{16}$

Q.

Fully eclipsed conformation of butane is :

1. 

2. 

3. 

4. 

Q. A straight chain alkane is formed out of ten carbon atoms. How many hydrogen atoms will be there in that molecule?

1. 40
2. 20
3. 22
4. 21