CBSE Class 11 Chemistry Chemical Bonding and Molecular Structure Assignment

Chemical Bonding and Molecular Structure MCQ Questions with Answers Class 11 Chemistry

Question. In a regular octahedral molecule, MX₆ the number of X – M – X bonds at 180º is

(1) Three

(2) Two

(3) Six

(4) Four

Answer (1)

Question. In which of the following molecules all the bonds are not equal?

(1) NF₃

(2) CI₃

(3) BF₃

(4) PF₃

Answer (2)

Question. Which species does not exhibit paramagnetism?

(1) N ₂⁺

(2) O₂^–

(3) CO

(4) NO

Answer (3)

Question. Which of the following molecule stabilizes by removal of electron?

(1) C₂

(2) O₂

(3) N₂

(4) H₂

Answer (2)

Question. Which of the following statement is correct?

(1) The hybridisation of Cl in ClF₃ is sp ²

(2) The number of lone pairs and bond pairs in I 3 – are 2 and 2 respectively

(3) The shape of XeF₆ is distorted square bipyramidal

(4) Hybridisation of S is sp ³ in SO ₂

Answer (3)

Question. In NO₃ ^– ion number of bond pair and lone pair of electrons on nitrogen atom are

(1) 2, 2

(2) 3, 1

(3) 1, 3

(4) 4, 0

Answer (4)

Question. Which of the following is correct for XeO₂F₂ and PCl₅ ?

(1) Both have same hybridisation and shape

(2) Both have same hybridisation but different geometry

(3) Both have different hybridisation but same shape

(4) Both have same hybridisation but different shape

Answer (4)

Question. Number of nodal planes in π*2px are

(1) Zero

(2) One

(3) Two

(4) Three

Answer (3)

Question. Which of the following is not a correct statement?

(1) Multiple bonds are always shorter than corresponding single bonds

(2) The electron-deficient molecules can act as Lewis acids

(3) The canonical structures have no real existence

(4) Every AB₅ molecules does in fact have square pyramid structure

Answer (4)

Question.  A certain diatomic molecule, AB has dipole moment 1.6 D and the internuclear distance is 100 pm. The percentage of electronic charge existing on more electronegative atom is

(1) 33%

(2) 25%

(3) 50%

(4) 10%

Answer (1)

Question. The maximum number of 180° angle possible between X-M-X bond for compounds with sp³ d ² and sp ³ d hybridisation respectively are

(1) 3, 3

(2) 3, 1

(3) 1, 3

(4) 3, 0

Answer (2)

Question. The hybrid orbital having only 20% d character

(1) CCl₄

(2) SF₆

(3) SF₄

(4) Cl₂O

Answer (3)

 ONE MARK QUESTIONS

1. Atomic orbital is monocentric while a molecular orbital is polycentric”. Explain

2. Explain the term resonance.

3. HF has a higher boiling point than HCl.why?

4. Define hybridization.

5. Write electron dot structures of CO₂ and AlCl₃.

TWO MARKS QUESTIONS

1 Define the term bond length. Arrange the following in the increasing order of their bond lengths: Ethane, ethene, ethyne

2 Define the term bond angle. Arrange the following in the increasing order of their bond angle: Water, ammonia, methane, carbon dioxide.

3 Which hybrid orbitals are used by the carbon atoms in the following molecules?
a. CH₃-CH=CH₂
b. CH₃-CH₂-OH

3 Which hybrid orbitals are used by the carbon atoms in the following molecules?
a. CH₃-CH=CH₂
b. CH₃-CH₂-OH
c. CH₃CHO
d. CH₃COOH

4 What do you understand by formal charge of a molecule? Calculate the formal charges
on all the atoms in the following molecules
i. HClO₄
ii. HSO₄
5 Differentiate between Bond energy and Bond dissociation energy

THREE MARKS QUESTIONS

1 What are
a) expanded octet molecules?
b) odd electron molecules?
c) Electron deficient molecules?
Give two examples for each.

2 Differentiate between
b) Covalent and Van der Waal’s radius
c) Bonding and antibonding molecular orbital.

3 Draw the resonating structures for the following :
CO₃^2- , NO₃- , SO₂

4 Give reasons:
a) BF₃ is non-polar while NF3 is polar.
b) ClF₃ is T-shaped.
c) px orbital does not overlap with py orbital.

5 Justify the following
a) Bonds in ozone are equivalent.
b) Oxygen is paramagnetic.
c) Acetic acid forms dimer.

6 Explain why
a) Para nitro phenol has higher boiling point than ortho nitro phenol.
b) Hydrogen bonding in HCl is insignificant.
c) Bond angle in water is larger than bond angle in H2S

7 Explain the formation of PCl5 and SF6 on the basis of hybridization.

8 Write the molecular orbital electronic configuration for O₂- and O₂⁺, Calculate the bond order & comment on their stabilities.

9 Draw orbital overlap diagram for the following:
a)H₃O⁺
b) H₂O
c) NH₃

10 Which hybrid orbitals are used by the carbon atoms in the following molecules?
a. CH₃-CH = CH₂
b. CH₃-CH₂-OH
c. CH₃CHO
d. CH₃COOH

VALUE BASED QUESTION( FOUR MARKS)

1 The Chemistry teacher was explaining the properties of two hydrides of Sulphur and Oxygen:
H₂S and H₂O. H₂S and H2O are having same hybridization states but different bond angles. H₂S
has indefinite volume while H₂O has definite volume. H2S cannot be placed in an open
container but H₂O can be placed due to their different physical states.
(i) Write the hybridization states of central atom in H2S and H₂O.
(ii) What are the physical states ofH₂S and H₂O?
(iii) Write bond angle of H₂O.
(iv) Why H₂S and H₂O have different bond angles .