   Chapter 9, Problem 47GQ

Chapter
Section
Textbook Problem

The CN molecule has been found in interstellar space. Assuming the electronic structure of the molecule can be described using the molecular orbital energy level diagram in Figure 9.16, answer the following questions.(a) What is the highest energy occupied molecular orbital (HOMO) to which an electron (or electrons) is (are) assigned?(b) What is the bond order of the molecule?(c) How many net σ bonds are there? How many net π bonds?(d) Is the molecule paramagnetic or diamagnetic?

(a)

Interpretation Introduction

Interpretation:

The highest energy occupied molecular orbital (HOMO) and the electron assigned in to it should be determined.

Concept Introduction:

Molecular orbital (MO) theory:  is a method for determining molecular structure in which electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule.

According to this theory there are two types of orbitals,

1. (1) Bonding orbitals
2. (2) Antibonding orbitals

Electrons in molecules are filled in accordance with the energy; the anti-bonding orbital has more energy than the bonding orbitals.

The electronic configuration of oxygen molecule O2 can be represented as follows,

(σ1s)2(σ*1s)2(σ2s)2(σ*2s)2(σ2p)2( π2p)4( π*2p)2

The * represent the antibonding orbital

HOMO and LUMO: This statement stand for highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), respectively. So this energy difference between the HOMO and LUMO is termed the HOMO–LUMO gap.

Explanation

Molecular orbital diagram of (CN) molecule can be drawn as

σ*2pz(Antibondingelectrons)π*2pπ*2p2px2py2pz2px2py2pzȀ

(b)

Interpretation Introduction

Interpretation:

Bond order of the given molecule should be determined.

Concept Introduction:

Molecular orbital (MO) theory:  is a method for determining molecular structure in which electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule.

According to this theory there are two types of orbitals,

1. (3) Bonding orbitals
2. (4) Antibonding orbitals

Electrons in molecules are filled in accordance with the energy; the anti-bonding orbital has more energy than the bonding orbitals.

The electronic configuration of oxygen molecule O2 can be represented as follows,

(σ1s)2(σ*1s)2(σ2s)2(σ*2s)2(σ2p)2( π2p)4( π*2p)2

Bond order: It is the measure of number of electron pairs shared between two atoms.

Bondorder=12(NumberofelectronsinbondoingMOs-NumberofelectronsinantibondingMOs)

The * represent the antibonding orbital

(c)

Interpretation Introduction

Interpretation:

Number of net σandπ bonds in the given molecule should be determined.

Concept Introduction:

Molecular orbital (MO) theory:  is a method for determining molecular structure in which electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule.

According to this theory there are two types of orbitals,

1. (1) Bonding orbitals
2. (2) Antibonding orbitals

Electrons in molecules are filled in accordance with the energy; the anti-bonding orbital has more energy than the bonding orbitals.

The electronic configuration of oxygen molecule O2 can be represented as follows,

(σ1s)2(σ*1s)2(σ2s)2(σ*2s)2(σ2p)2( π2p)4( π*2p)2

Bond order: It is the measure of number of electron pairs shared between two atoms.

Bondorder=12(NumberofelectronsinbondoingMOs-NumberofelectronsinantibondingMOs)

The * represent the antibonding orbital

Sigma (σ) bonds are the bonds in which shared hybrid orbital’s electron density are concentrated along the internuclear axis.

Pi (π) bonds are the bonds in which shared unhybridized orbital’s (p, d, etc) electron density are concentrated in above and below of the plane of the molecule.

(d)

Interpretation Introduction

Interpretation:

It should be checked that whether the CN molecule is paramagnetic or diamagnetic in nature.

Concept Introduction:

Molecular orbital (MO) theory:  is a method for determining molecular structure in which electrons are not assigned to individual bonds between atoms, but are treated as moving under the influence of the nuclei in the whole molecule.

According to this theory there are two types of orbitals,

1. (1) Bonding orbitals
2. (2) Antibonding orbitals

Electrons in molecules are filled in accordance with the energy; the anti-bonding orbital has more energy than the bonding orbitals.

The electronic configuration of oxygen molecule O2 can be represented as follows,

(σ1s)2(σ*1s)2(σ2s)2(σ*2s)2(σ2p)2( π2p)4( π*2p)2

Atoms with unpaired electrons are called Paramagnetic. Paramagnetic atoms are attracted to a magnet.

Atoms with paired electrons are called diamagnetic. Diamagnetic atoms are repelled by  a magnet.

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Find more solutions based on key concepts 