Chemical Bonding And Molecular Structure CBSE Questions & Answers

Chemical Bonding And Molecular Structure

This is Chemistry Class 11 Chemical Bonding and Molecular Structure CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

Polarity in a molecule and hence the dipole moment depends primarily on electronegativity of the constituent atoms and shape of a molecule. Which of the following has the highest dipole moment?

A
${\text{C}}{{\text{O}}_{\text{2}}}$
B
${{\text{H}}_{\text{2}}}{\text{O}}$
Correct
C
${\text{S}}{{\text{O}}_{\text{2}}}$
D
HI

The types of hybrid orbitals of nitrogen in${\text{No}}_2^ + $, ${\text{No}}_3^ - $ and N${\text{H}}_4^ + $ respectively are expected to be

A
sp, ${\text{s}}{{\text{p}}^{\text{3}}}$and ${\text{s}}{{\text{p}}^{\text{2}}}$
Correct
B
${\text{s}}{{\text{p}}^{\text{2}}}$, sp and ${\text{s}}{{\text{p}}^{\text{3}}}$
C
sp, ${\text{s}}{{\text{p}}^{\text{2}}}$ and ${\text{s}}{{\text{p}}^{\text{3}}}$
D
${\text{s}}{{\text{p}}^{\text{2}}}$, ${\text{s}}{{\text{p}}^{\text{3}}}$and sp.

Isostructural species are those which have the same shape and hybridisation. Among the given species identify the isostructural pairs.

A
$\left[ {{\text{N}}{{\text{F}}_{\text{3}}}{\text{and B}}{{\text{F}}_{\text{3}}}} \right]$
B
$\left[ {{\text{BC}}{{\text{l}}_{\text{3}}}{\text{and BrC}}{{\text{l}}_{\text{3}}}} \right]$
C
$[NH3andNo_3^ - ]$
D
$[BF4 - andNH_4^ + ]$
Correct

In ${\text{NO}}_3^ - $ ion, the number of bond pairs and lone pairs of electrons on nitrogen atom are

A
1, 3
B
3, 1
C
4, 0
Correct
D
2, 2

Amongst the following elements whose electronic configurations are given below, the one having the highest ionisation enthalpy is

A
$\left[ {{\text{Ne}}} \right]{\text{ 3}}{{\text{s}}^{\text{2}}}{\text{3 }}{{\text{p}}^{\text{2}}}$
B
$\left[ {{\text{Ne}}} \right]{\text{ 3}}{{\text{s}}^{\text{2}}}{\text{3}}{{\text{p}}^{\text{1}}}$
C
$\left[ {{\text{Ar}}} \right]{\text{ 3}}{{\text{d}}^{{\text{1}}0}}{\text{4}}{{\text{s}}^{\text{2}}}{\text{4 }}{{\text{p}}^{\text{3}}}$
D
$\left[ {{\text{Ne}}} \right]{\text{ 3}}{{\text{s}}^{\text{2}}}{\text{3p3}}$
Correct

Species having same bond order are :

A
${\text{F}}_2^ + $ and ${\text{N}}_2^ + $
B
${\text{O}}_2^ - $ and ${\text{N}}_2^ - $
C
${{\text{N}}_2}$ and ${\text{N}}_2^ - $
D
${\text{F}}_2^ + $ and ${\text{O}}_2^ - $
Correct

Which of the following statements are not correct?

A
VSEPR Theory can explain the square planar geometry of ${\text{Xe}}{{\text{F}}_{\text{4}}}$.
B
NaCl being an ionic compound is a good conductor of electricity in the solid state.
Correct
C
Hybrid orbitals form stronger bonds than pure orbitals.
D
In canonical structures there is no difference in the arrangement of atoms.

Rank the bonds in the set C=O, C-O, C$ \equiv $O in order of decreasing bond length

A
C-O > C=O > C$ \equiv $O
Correct
B
C$ \equiv $O< C-O > C=O
C
C=O > C$ \equiv $O <C-O
D
C-O > C$ \equiv $O > C=O

Rank the bonds in the set C=O, C-O, C$ \equiv $O in order of decreasing bond strength

A
C$ \equiv $O > C=O > C-O
Correct
B
C=O < C$ \equiv $O > C-O
C
C-O < C$ \equiv $O > C=O
D
C$ \equiv $O > C-O < C=O

Quartz is very hard and melts at${\text{1 55}}0^\circ {\text{C}}$. Reason is:

A
separate $Si0_2$ molecules exist that are held together by pi bonds that extend in three dimensions throughout the sample
B
Quartz ($Si0_2$) has silicon-oxygen electrovalent bonds that extend throughout the sample
C
Quartz ($Si0_2$) has silicon-oxygen covalent bonds that extend throughout the sample
Correct
D
separate $Si0_2$ molecules exist they are held together by coordinate bonds that extend throughout the sample

Rank the following bonds in order of increasing polarity: H-N, H-O, H-C.

A
H-N < H-O < H-C
B
H - C < H-N < H-O.
Correct
C
H-O < H-N < H-C
D
H - C < H-O < H-N.

The electronegativity difference $\left( {\Delta {\text{EN}}} \right)$ is large in one of the following.

A
Two metals
B
H-H
C
metal and a nonmetal
Correct
D
Two nonmetals

$N_2$, CO and ${\text{N}}{{\text{O}}^ + }$ are isoelectronic molecules. Their respective bond order is :

A
1,1,3
B
3,3,3
Correct
C
2,3,4
D
2,3,3

Bond order of ${\text{O}}_2^ + $ and ${\text{O}}_2^ - $ are

A
1.1 and 2.5
B
2.5 and 1. 5
Correct
C
3.2 and 2.5
D
2.4 and 1.3

NaCl does not conduct electricity in the but do conduct it when melted

A
when dissolved in water
B
solid state
Correct
C
when kept at low temperatures
D
molten state