NCERT Activity 4.2 Class 10 Science Explanation with a conclusion

If you are looking for NCERT Science Class 10 Chapter 4 Activity solutions, then you are at the right place. In this post, you will find NCERT Activity 4.2 Class 10 Science Explanation with a conclusion.

NCERT Activity 4.2 Class 10 Science Explanation with a Conclusion

You are suggested to study NCERT activity 4.2 class 10 science explanation with a conclusion so that you can attempt questions based on activity 4.2 class 10 science.

 

Chapter 4 - Carbon and its Compounds

 

Activity 4.2 Class 10 Science

·      Calculate the difference in the formulas and molecular masses for (a) CH₃OH and C₂H₅OH (b) C₂H₅OH and C₃H₇OH and (c) C₃H₇OH and C₄H₉OH.

·      Is there any similarity between these three?

·      Arrange these alcohols in the order of increasing carbon atoms to get a family. Can we call this family a homologous series?

·      Generate the homologous series for compounds containing upto four carbons for the other functional groups given ahead table

Discussion

1.    

Compounds	Difference in formulae	Differences in molecular masses
CH3OH & C2H5OH	-CH2	14u
C2H5OH & C3H7OH	-CH2	14u
C3H7OH& C4H9OH.	-CH2	14u

2.   Yes, all these compounds have -OH group.

3.   CH₃OH , C₂H₅OH ,  C₃H₇OH,  C₄H₉OH.

All these compounds have -OH group so they are a family and we can call this family a homologous series because they show a difference in -CH₂.

4.   the homologous series for compounds containing up to four carbons for the other functional groups are given table below

1.   chloro group – CH₃Cl, C₂H₅Cl , C₃H₇Cl , C₄H₉Cl

2.   aldehyde group- CH₃CHO, CH₃CHO, CH₃CHO, CH₃CHO

3.   ketone group – CH₃COCH₃  , CH₃CH₂COCH₃, CH₃CH₂CO CH₂CH₃ , CH₃CH₂CH₂CO CH₂CH₂CH₃

4.   carboxylic acid  - CH₃COOH, C₂H₅COOH, C₃H₇COOH,

C₄H₉COOH

 

Conclusion -  Now from the above discussion, it is clear that the common difference in the molecular formula is -CH₂  and molecular mass is 14u. 

Question-based on activity 4.2 Class 10 Science

1. What is a homologous series?

Ans.- A series or group of organic compounds having similar structural formulae, same functional group, and same chemical properties is called a homologous series.

2. What is the importance of a homologous series?

Ans.- (i) It helps in a systematic study of organic compounds.

(ii) We can predict the properties of all the members of a homologous series when we identify the properties of any member.

Related Topics - 

1. Activity 4.3 Class 10 Science

2.  Activity 4.1 Class 10 Science

3. Solution of Chapter 4 Carbon and its Compounds

4. MCQ Questions of Chapter 4

5. Extra Questions of Chapter 4

6. Solutions of Class 10 Science all chapters