NCERT Solutions for Class 11 Chemistry Chapter 4 – Chemical Bonding and Molecular Structure

Chemistry Ncert Solutions Class 11th 2023

Pallavi Pathak
Updated on Sep 18, 2025 12:42 IST

By Pallavi Pathak, Assistant Manager Content

NCERT Solutions for Class 11 Chemistry Chapter 4: Chemical Bonding and Molecular includes all the exercise questions given in the textbook. It discusses the attractive force that holds various constituents together in different chemical species. A chemical bond holds atoms and ions together in a molecule.
Chemical Bonding Class 11 covers the Valence Shell Electron Pair Repulsion (VSEPR) Theory, the Kössel-Lewis approach, the VSEPR model, Molecular Orbital (MO) Theory, and Valence Bond (VB) Theory. Chemical Bonding Class 11 NCERT Solutions is created by the subject matter experts. All the solutions are given in a step-by-step format. It is easy to understand and helps students build their problem-solving skills. The solutions are accurate and reliable for CBSE Board exam preparation and for preparing for various competitive exams, such as NEET and JEE Main.
Get free NCERT Solutions for Class 11 and 12 in Maths, Physics, and Chemistry, and chapter-wise PDFs with key concepts simplified for easy learning, available here - NCERT Solutions Class 11 and 12 for Maths, Physics, Chemistry.

Table of content
  • Chemical Bonding and Molecular Structure Question and Answers
  • Class 11 Chemistry Chemical Bonding and Molecular Structure: Key Topics, Weightage
  • Important Formulae of Chemical Bonding and Molecular Structure
  • Class 11 Chemistry Chemical Bonding and Molecular Structure Solution PDF: Download PDF for Free
  • Chemical Bonding and Molecular Structure - FAQs
Chemistry Ncert Solutions Class 11th Logo

Chemical Bonding and Molecular Structure Question and Answers

Students can find the NCERT solutions for Class 11 Chemistry Chapter 4 Chemical Bonding and Molecular Structure for the intext questions.

4.1. Explain the formation of a chemical bond.
Answer: Chemical bond is an attractive force which binds atoms, ions etc. together in a compound. According to Kossel and Lewis, atoms combine together in order to complete their respective octets so as to acquire the configuration of the nearest stable inert gas. This can occur in two ways; by transfer of one or more electrons from one atom to other or by sharing of electrons between two or more atoms. The chemical bond formed by sharing of electrons is called a covalent bond. In this process a chemical bond is formed
4.2. Write Lewis dot symbols for atoms of the following elements: Mg, Na, B, O, N, Br.         

Answer:

Element

Atomic number

Atomic arrangement

Lewis symbol

Mg

12

2,8,2

 

Na

11

2,8,1

 

B

5

2,3

 

O

8

2,6

 

N

7

2,5

 

Br

35

2,8,18,7

 
4.3. Write Lewis symbols for the following atoms and ions: S and S2–; Al and Al3+; H and H. (Beginner)

Answer:

16S = 2, 8, 6

13Al = 2, 8, 3

1H = 1

Lewis symbols are:

4.4. Draw the Lewis structures for the following molecules and ions:
H2S, SiCl4, BeF2, CO32-, HCOOH.                                                                                            

Answer:

 

The properties of molecules and compounds are determined by their molecular structure, which is the arrangement of the atoms in space. The molecular structure is determined by the type of bond and the number and arrangement of atoms in the molecule. The shape of the molecule affects its polarity, reactivity, and physical properties such as boiling point, melting point, and solubility.

The valence shell electron pair repulsion (VSEPR) theory is a model used to predict the molecular structure of covalent molecules based on the repulsion between valence electron pairs. This theory states that the electron pairs in the valence shell of an atom repel each other and try to occupy positions that minimise repulsion. The VSEPR theory is used to predict the geometry and shape of molecules, such as linear, trigonal planar, tetrahedral, and octahedral.

In summary, chemical bonding and molecular structure are important concepts in chemistry that help us understand the behaviour and properties of molecules and compounds. The type of bond and molecular structure determine the properties of a substance, including its reactivity, polarity, and physical properties. The VSEPR theory is a useful tool for predicting the molecular structure of covalent molecules based on the repulsion between valence electron pairs.

 AsF5​

 5

AB5

 

 trigonal bipyramidal

 three 120 o, two 90 o

 H2​S

 6

AB2L2

 

V-shaped/bent

  92 o

 PH3

 5

AB3L

 

 trigonal pyramidal

  93.5o

Q&A Icon
Commonly asked questions
Q:  

4.4. Draw the Lewis structures for the following molecules and ions:

H2S, SiCl4, BeF2, CO32-, HCOOH.   

Read more
Q:  

4.14. Use Lewis symbols to show electron transfer between the following atoms to form cations and anions (a) K and S (b) Ca and O (c) Al and N. 

Read more
Q:  

4.27. Draw diagrams showing the formation of a double bond and a triple bond between carbon atoms in C2H4 and C2Hmolecules.

Read more
Q:  

4.7. Discuss the shape of the following molecules using the VSEPR model:

BeCl2, BCl3, SiCl4, AsF5, H2S, PH3.

Read more
Q:  

4.6. Write the favourable factors for the formation of ionic bond.

Q:  

4.10. Define the bond-length.

Q:  

4.11. Explain the important aspects of resonance with reference to the CO32-ion.

Q:  

4.16. Write the significance/applications of dipole moment.

Q:  

4.17. Define electronegativity. How does it differ from electron gain enthalpy?

Q:  

4.25. Describe the change in hybridisation (if any) of the Al atom in the following reaction.  

AlCl3 + Cl ——> AlCl4- 

Read more
Q:  

4.31. What do you understand by bond pairs and lone pairs of electrons? Illustrate by giving one example of each type.

Read more
Q:  

4.33. Explain the formation of H2 molecule on the basis of valence bond theory.

Q:  

4.38. Describe the hybridisation in case of PCl5. Why are the axial bonds longer as compared to equatorial bonds?

Read more
Q:  

4.21. Apart from tetrahedral geometry, another possible geometry for CH4 is square planar with the four H atoms at the comers of the square and the C atom at its centre. Explain why CH4 is not square planar?

Read more
Q:  

4.22. Explain why BeH2 molecule has a zero dipole moment although the Be—H bonds are polar.

Q:  

4.26. Is there any change in the hybridisation of B and N atoms as a result of the following reaction?

BF3 + NH3 ——-> F3B.NH

Read more
Q:  

4.28. What is the total number of sigma and pi bonds in the following molecules?

(a) C2H2 

(b) C2H4

Read more
Q:  

4.29 Considering x-axis as the inter-nuclear axis which out of the following will not form a sigma bond and why?

(a) 1s and 1s

(b) 1s and 2px

(c) 2py and 2py

(d) 1s and 2s

Read more
Q:  

4.2. Write Lewis dot symbols for atoms of the following elements: Mg, Na, B, O, N, Br.  

Q:  

4.3. Write Lewis symbols for the following atoms and ions: S and S2–; Al and Al3+; H and H.

Read more
Q:  

 4.48. Which one is diamagnetic among NO+, NO and NO?

(a) NO+  

(b) NO           

(c) NO–  

(d) None of these

Read more
Q:  

4.47. The axial overlap between the two orbitals leads to the formation of a:

(a) Sigma bond

(b) Pi bond

(c) Multiple Bond

(d) None of these

Read more
Q:  

4.12. H3POcan be represented by structures 1 and 2 shown below. Can these two structures be taken as the canonical forms of the resonance hybrid representing H3PO3? If not, give reasons for the same.

Read more
Q:  

4.24. What is meant by hybridisation of atomic orbitals? Describe the shapes of sp, sp2, sp3 hybrid orbitals.

Read more
Q:  

4.35. Use molecular orbital theory to explain why the Be2 molecule does not exist.

Q:  

4.40. What is meant by the term bond order? Calculate the bond order of N2, O2, O2+ and O2.

Q:  

4.42. Assertion: In BF3, the dipole moment is zero

Reason: The three bond moments give anet sum of zero as the resultant of any two is equal and opposite to the third.

Read more
Q:  

4.9. How do you express the bond strength in terms of bond order?            

Read more
Q:  

4.46. A co-ordinate bond is formed by:

(a) Sharing of electrons contributed by both the atoms

(b) Complete transfer of electrons

(c) Sharing of electrons contributed by one atom only

(d) None of these

Read more
Q:  

4.53. What is meant by bond pairs of electrons?

Q:  

4.1. Explain the formation of a chemical bond.

Q:  

4.5. Define Octet rule. Write its significance and limitations.

Q:  

4.8. Although geometries of NHand H2O molecules are distorted tetrahedral, bond angle in water is less than that of ammonia. Discuss.

Read more
Q:  

4.32. Distinguish between a sigma bond and a pi bond.

Q:  

4.34. Write the important conditions required for the linear combination of atomic orbitals to form molecular orbitals.

Read more
Q:  

4.41. Assertion: The dipole moment in case of BeF2 is zero.

Reason: There are two F atoms in a molecule of BeF2.

Read more
Q:  

4.15. Although both CO2 and H2O are tri atomic molecules, the shape of H2O molecule is bent while that of CO2 is linear. Explain this on the basis of dipole moment.

Read more
Q:  

4.18. Explain with the help of suitable example polar covalent bond.

Q:  

4.19. Arrange the bonds in order of increasing ionic character in the molecules: LiF, K2O, N2, SO2 and ClF3.

Read more
Q:  

4.23. Which out of NH3 and NF3 has higher dipole moment and why?         

Read more
Q:  

4.36. Compare the relative stability of the following species and indicate their magnetic properties: O2, O2, O2 (Superoxide), O22- (peroxide)

Read more
Q:  

4.37. Write the significance of plus and minus sign in representing the orbitals.

Q:  

4.39. Define hydrogen bonds. Is it weaker or stronger than the van der Waals forces?

Q:  

4.43. Assertion: Sigma bond is weaker as compared to the pi bond.

Reason: The overlapping of orbitals takes place to a larger extent in sigma bond while the extent of overlapping occurs to a smaller extent in case of pi bond.

Read more
Q:  

4.44. Assertion: A bonding molecular orbital always possesses lower energy than either of the atomic orbitals that have combined to form it.

Reason: Electrons placed in a bonding molecular orbital tend to destabilise a molecule.

Read more
Q:  

4.45. Assertion: In PCl5, the axial bonds are slightly longer and hence slightly weaker than the equatorial bonds.

Reason: The axial bond pairs suffer more repulsive interaction from the equatorial bond pairs.

Read more
Q:  

4.49. Out of the following, intramolecular hydrogen bonding exists in:

(a) Water

(b) H2S

(c) 4-nitrophenol

(d) 2-nitrophenol

Read more
Q:  

4.50. Relation between bond order and stability of a molecule:

(a) Lower the bond order, greater is the stability

(b) Not related to each other

(c) Higher the bond order, greater is the stability

(d) None of the above

Read more
Q:  

4.51. Write the type of hybridisation involved in CH4, C2H4 and C2H2.

Q:  

4.52. Predict the shapes of the following molecules using VSEPR theory?

(i) BeCl2

(ii) SiCl4

Q:  

4.54. Why ethyl alcohol is completely miscible with water?

Q:  

4.55. Which is more polar CO2 or N2O? Give reason.

Q:  

4.56. Why N2 is more stable than O2? Explain on the basis of molecular orbital theory.

Q:  

4.57. Out of bonding and antibonding molecular orbitals, which one has lower energy and which one has higher stability?

Read more
Q:  

4.58. Name the two conditions which must be satisfied for hydrogen bonding to take place in a molecule.

Read more
Q:  

4.59. What are Lewis structures? Write the Lewis structure of H2, BeF2 and H2O.

Q:  

4.60. Define Lattice energy. How is Lattice energy influenced by

(i) Charge on the ions

(ii) Size of the ions?

Read more
Q:  

4.13. Write the resonance structures for SO3, NO2 and NO3.         

Read more
Q:  

4.20 The skeletal structure of CH3COOH as shown below is correct, but some of the bonds are shown incorrectly. Write the correct Lewis structure for acetic acid.

Read more
Q:  

4.30. Which hybrid orbitals are used by carbon atoms in the following molecules?

(a) CH3-CH3 (b) CH3-CH=CH2 (c) CH3-CH2-OH (d) CH3-CHO (e) CH3COOH.

Read more
Chemistry Ncert Solutions Class 11th Logo

Class 11 Chemistry Chemical Bonding and Molecular Structure: Key Topics, Weightage

Class 11 Chapter 4 Chemical Bonding and Molecular Structure explores various key topics that help in understanding the chemical compound formation through various reaction mechanisms and molecular structures.

Before starting any chapter preparation, it is good to see the topics covered in the chapter for planned learning.

The following are the topics covered in this chapter:

Exercises Topics Covered
4.1 Kossel-Lewis Approach to Chemical Bonding
4.2 Ionic or Electrovalent Bond
4.3 Bond Parameters
4.4 The Valence Shell Electron Pair Repulsion (VSEPR) Theory
4.5 Valence Bond Theory
4.6 Hybridisation
4.7 Molecular Orbital Theory
4.8 Bonding in Some Homonuclear Diatomic Molecules
4.9 Hydrogen Bonding

Chemical Bonding and Molecular Structure Weightage in NEET and JEE Main exam

Examination Number of Questions Weightage
NEET 2-3 questions 8-10%
JEE Main 2 questions 6-8%

Try these practice questions

Q1:

Match List – I with List – II                                     &nbs

View Full Question

Q2:

A student needs to prepare a buffer solution of propanoic acid and its sodium salt with pH 4. The ratio of [ C H 3 C H 2 C O O ] [ C H 3 C H 2 C O O H ] required to make buffer is_________.

Given :  K a ( C H 3 C H 2 C O O H ) = 1 . 3 × 1 0 5

View Full Question

Q3:

Which of the following pair of molecules contain odd electron molecule and an expanded octet molecule?

Chemistry Ncert Solutions Class 11th Logo

Important Formulae of Chemical Bonding and Molecular Structure

Important Formulae of Chemical Bonding and Molecular Structure for CBSE and Competitive Exams

  1. Formal Charge Calculation:

    Formal Charge = ( Valence electrons ) ( Non-bonding electrons ) 1 2 ( Bonding electrons ) \text{Formal Charge} = \left( \text{Valence electrons} \right) - \left( \text{Non-bonding electrons} \right) - \frac{1}{2} \left( \text{Bonding electrons} \right)
  2. Bond Order (MOT):

    Bond Order = ( Number of bonding electrons ) ( Number of antibonding electrons ) 2 \text{Bond Order} = \frac{(\text{Number of bonding electrons}) - (\text{Number of antibonding electrons})}{2}
  3. Dipole Moment:

    μ = q × d \mu = q \times d
  4. Hybridization Formula:

    Hybridization Number = 1 2 ( Valence electrons of central atom + Number of monovalent atoms Charge on cation + Charge on anion )

 

Chemistry Ncert Solutions Class 11th Logo

Class 11 Chemistry Chemical Bonding and Molecular Structure Solution PDF: Download PDF for Free

Download PDF from the link below:

Class 11 Chemistry Chapter 4 Chemical Bonding and Molecular Structure NCERT Solution PDF: Download Free PDF

Chemistry Ncert Solutions Class 11th Logo

Chemical Bonding and Molecular Structure - FAQs

These are the frequently asked questions from the chemical bonding class 11:

 

Q&A Icon
Commonly asked questions
Q:  

In Chemical bonding, what are the four types of bonds?

Q:  

Explain the concept of chemical bonding.

Q:  

According to bonding chemistry, what are different types of chemical bonds?

Q:  

Mention three types of chemical bonds.

Q:  

In Chemical Bonding and Molecular Structure, which are three types of chemical laws?

Explore exams which ask questions on Chemistry Ncert Solutions Class 11th

Select your preferred stream

qna

Chemistry Ncert Solutions Class 11th Exam

Student Forum

chatAnything you would want to ask experts?
Write here...