General Chemistry
General Chemistry
7th Edition
ISBN: 9780073402758
Author: Chang, Raymond/ Goldsby
Publisher: McGraw-Hill College
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Chapter 7, Problem 7.61QP

(a)

Interpretation Introduction

Interpretation:

The total number of electrons which can occupy in s, p, d and f-orbitals should be identified using the concept of quantum numbers.

Concept Introduction

Quantum Numbers

Quantum numbers are explained for the distribution of electron density in an atom. They are derived from the mathematical solution of Schrodinger’s equation for the hydrogen atom.  The types of quantum numbers are the principal quantum number (n), the angular momentum quantum number (l), the magnetic quantum number (ml) and the electron spin quantum number (ms). Each atomic orbital in an atom is categorized by a unique set of the quantum numbers.

Principal Quantum Number (n)

The principal quantum number (n) assigns the size of the orbital and specifies the energy of an electron.  If the value of n is larger, then the average distance of an electron in the orbital from the nucleus will be greater.  Therefore the size of the orbital is large. The principal quantum numbers have the integral values of 1, 2, 3 and so forth and it corresponds to the quantum number in Bohr’s model of the hydrogen atom.  If all orbitals have the same value of ‘n’, they are said to be in the same shell (level).  The total number of orbitals for a given n value is n2.  As the value of ‘n’ increases, the energy of the electron also increases.

Angular Momentum Quantum Number (l)

The angular momentum quantum number (l) explains the shape of the atomic orbital.  The values of l are integers which depend on the value of the principal quantum number, n.  For a given value of n, the possible values of l range are from 0 to n − 1.  If n = 1, there is only one possible value of l (l=0).  If n = 2, there are two values of l: 0 and 1.  If n = 3, there are three values of l: 0, 1, and 2.  The value of l is selected by the letters s, p, d, and f.  If l = 0, we have an s orbital; if l = 1, we have a p orbital; if l = 2, we have a d orbital and finally if l = 3, we have a f orbital.  A collection of orbitals with the same value of n is called a shell.  One or more orbitals with the same n and l values are referred to a subshell (sublevel).  The value of l also has a slight effect on the energy of the subshell; the energy of the subshell increases with l (s < p < d < f).

Magnetic Quantum Number (ml)

The magnetic quantum number (ml) explains the orientation of the orbital in space.  The value of ml depends on the value of l in a subshell.  This number divides the subshell into individual orbitals which hold the electrons.  For a certain value of l, there are (2l + 1) integral values of ml which is explained as follows:

ml = ‒ l, ..., 0, ..., +l

If l = 0, there is only one possible value of ml: 0.

If l = 1, then there are three values of ml: −1, 0, and +1.

If l = 2, there are five values of ml, namely, −2, −1, 0, +1, and +2.

If l = 3, there are seven values of ml, namely, −3, −2, −1, 0, +1, +2, and +3, and so on.

The number of ml values indicates the number of orbitals in a subshell with a particular l value.  Therefore, each ml value refers to a different orbital.

Electron Spin Quantum Number (ms)

It specifies the orientation of the spin axis of an electron.  An electron can spin in only one of two directions.  There are two possible ways to represent ms values.  They are +½ and ‒½.  One electron spins in the clockwise direction.  Another electron spins in the anticlockwise direction.  But, no two electrons should have the same spin quantum number.

Pauli Exclusion Principle

No two electrons in an atom should have the four same quantum numbers.  Two electrons are occupied in an atomic orbital because there are two possible values of ms.  As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.  If two electrons have the same values of n, l and ml values, they should have different values of ms

To find: Count the total number of electrons which can occupy in one s-orbital

Find the value of ‘l’ for one s-orbital

If the angular momentum quantum number (l) is 0, it corresponds to an s subshell for any value of the principal quantum number (n).

Find the value of ‘ml’ for one s-orbital

If l = 0, the magnetic quantum number (ml) has only one possible value which is again zero.  It corresponds to an s orbital.

Count the electrons in one s-orbital

(a)

Expert Solution
Check Mark

Answer to Problem 7.61QP

The total number of electrons which can occupy in one s-orbital is 2 (a).

Explanation of Solution

There is an s subshell in every shell and each s subshell contains just one orbital.  In one orbital, there are two electrons are occupied.  Therefore, the total number of electrons which can occupy in one s-orbital is 2.

(b)

Interpretation Introduction

Interpretation:

The total number of electrons which can occupy in s, p, d and f-orbitals should be identified using the concept of quantum numbers.

Concept Introduction

Quantum Numbers

Quantum numbers are explained for the distribution of electron density in an atom. They are derived from the mathematical solution of Schrodinger’s equation for the hydrogen atom.  The types of quantum numbers are the principal quantum number (n), the angular momentum quantum number (l), the magnetic quantum number (ml) and the electron spin quantum number (ms). Each atomic orbital in an atom is categorized by a unique set of the quantum numbers.

Principal Quantum Number (n)

The principal quantum number (n) assigns the size of the orbital and specifies the energy of an electron.  If the value of n is larger, then the average distance of an electron in the orbital from the nucleus will be greater.  Therefore the size of the orbital is large. The principal quantum numbers have the integral values of 1, 2, 3 and so forth and it corresponds to the quantum number in Bohr’s model of the hydrogen atom.  If all orbitals have the same value of ‘n’, they are said to be in the same shell (level).  The total number of orbitals for a given n value is n2.  As the value of ‘n’ increases, the energy of the electron also increases.

Angular Momentum Quantum Number (l)

The angular momentum quantum number (l) explains the shape of the atomic orbital.  The values of l are integers which depend on the value of the principal quantum number, n.  For a given value of n, the possible values of l range are from 0 to n − 1.  If n = 1, there is only one possible value of l (l=0).  If n = 2, there are two values of l: 0 and 1.  If n = 3, there are three values of l: 0, 1, and 2. The value of l is selected by the letters s, p, d, and f.  If l = 0, we have an s orbital; if l = 1, we have a p orbital; if l = 2, we have a d orbital and finally if l = 3, we have a f orbital.  A collection of orbitals with the same value of n is called a shell.  One or more orbitals with the same n and l values are referred to a subshell (sublevel).  The value of l also has a slight effect on the energy of the subshell; the energy of the subshell increases with l (s < p < d < f).

Magnetic Quantum Number (ml)

The magnetic quantum number (ml) explains the orientation of the orbital in space.  The value of ml depends on the value of l in a subshell.  This number divides the subshell into individual orbitals which hold the electrons.  For a certain value of l, there are (2l + 1) integral values of ml which is explained as follows:

ml = ‒ l, ..., 0, ..., +l

If l = 0, there is only one possible value of ml: 0.

If l = 1, then there are three values of ml: −1, 0, and +1.

If l = 2, there are five values of ml, namely, −2, −1, 0, +1, and +2.

If l = 3, there are seven values of ml, namely, −3, −2, −1, 0, +1, +2, and +3, and so on.

The number of ml values indicates the number of orbitals in a subshell with a particular l value.  Therefore, each ml value refers to a different orbital.

Electron Spin Quantum Number (ms)

It specifies the orientation of the spin axis of an electron.  An electron can spin in only one of two directions.  There are two possible ways to represent ms values.  They are +½ and ‒½.  One electron spins in the clockwise direction.  Another electron spins in the anticlockwise direction.  But, no two electrons should have the same spin quantum number.

Pauli Exclusion Principle

No two electrons in an atom should have the four same quantum numbers.  Two electrons are occupied in an atomic orbital because there are two possible values of ms.  As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.  If two electrons have the same values of n, l and ml values, they should have different values of ms

To find: Count the total number of electrons which can occupy in one p-orbital

Find the value of ‘l’ for one p-orbital

If the angular momentum quantum number (l) is 1, it corresponds to a p subshell for the principal quantum number (n) of 2 or greater values.

Find the value of ‘ml’ for one p-orbital

If l = 1, the magnetic quantum number (ml) has the three possible ways such as −1, 0 and +1 values.  It corresponds to three p-subshells.  They are labeled px, py, and pz with the subscripted letters indicating the axis along which each orbital is oriented.  The three p orbitals are identical in size, shape and energy; they differ from one another only in orientation. 

Count the electrons in one p-orbital.

(b)

Expert Solution
Check Mark

Answer to Problem 7.61QP

The total number of electrons which can occupy in one p-orbital is 6 (b).

Explanation of Solution

There are three p-subshells in every p-orbitals.  In one subshell, there are two electrons are occupied.  In p-orbital, (3 × 2) = 6 electrons are occupied.  Therefore, the total number of electrons which can occupy in one p-orbital is 6.

(c)

Interpretation Introduction

Interpretation:

The total number of electrons which can occupy in s, p, d and f-orbitals should be identified using the concept of quantum numbers.

Concept Introduction

Quantum Numbers

Quantum numbers are explained for the distribution of electron density in an atom. They are derived from the mathematical solution of Schrodinger’s equation for the hydrogen atom.  The types of quantum numbers are the principal quantum number (n), the angular momentum quantum number (l), the magnetic quantum number (ml) and the electron spin quantum number (ms). Each atomic orbital in an atom is categorized by a unique set of the quantum numbers.

Principal Quantum Number (n)

The principal quantum number (n) assigns the size of the orbital and specifies the energy of an electron.  If the value of n is larger, then the average distance of an electron in the orbital from the nucleus will be greater.  Therefore the size of the orbital is large. The principal quantum numbers have the integral values of 1, 2, 3 and so forth and it corresponds to the quantum number in Bohr’s model of the hydrogen atom.  If all orbitals have the same value of ‘n’, they are said to be in the same shell (level).  The total number of orbitals for a given n value is n2.  As the value of ‘n’ increases, the energy of the electron also increases.

Angular Momentum Quantum Number (l)

The angular momentum quantum number (l) explains the shape of the atomic orbital.  The values of l are integers which depend on the value of the principal quantum number, n.  For a given value of n, the possible values of l range are from 0 to n − 1.  If n = 1, there is only one possible value of l (l=0).  If n = 2, there are two values of l: 0 and 1.  If n = 3, there are three values of l: 0, 1, and 2.  The value of l is selected by the letters s, p, d, and f.  If l = 0, we have an s orbital; if l = 1, we have a p orbital; if l = 2, we have a d orbital and finally if l = 3, we have a f orbital.  A collection of orbitals with the same value of n is called a shell.  One or more orbitals with the same n and l values are referred to a subshell (sublevel).  The value of l also has a slight effect on the energy of the subshell; the energy of the subshell increases with l (s < p < d < f).

Magnetic Quantum Number (ml)

The magnetic quantum number (ml) explains the orientation of the orbital in space.  The value of ml depends on the value of l in a subshell.  This number divides the subshell into individual orbitals which hold the electrons.  For a certain value of l, there are (2l + 1) integral values of ml which is explained as follows:

ml = ‒ l, ..., 0, ..., +l

If l = 0, there is only one possible value of ml: 0.

If l = 1, then there are three values of ml: −1, 0, and +1.

If l = 2, there are five values of ml, namely, −2, −1, 0, +1, and +2.

If l = 3, there are seven values of ml, namely, −3, −2, −1, 0, +1, +2, and +3, and so on.

The number of ml values indicates the number of orbitals in a subshell with a particular l value.  Therefore, each ml value refers to a different orbital.

Electron Spin Quantum Number (ms)

It specifies the orientation of the spin axis of an electron.  An electron can spin in only one of two directions.  There are two possible ways to represent ms values.  They are +½ and ‒½.  One electron spins in the clockwise direction.  Another electron spins in the anticlockwise direction.  But, no two electrons should have the same spin quantum number.

Pauli Exclusion Principle

No two electrons in an atom should have the four same quantum numbers.  Two electrons are occupied in an atomic orbital because there are two possible values of ms.  As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.  If two electrons have the same values of n, l and ml values, they should have different values of ms

To find: Count the total number of electrons which can occupy in one d-orbital

Find the value of ‘l’ for one d-orbital

If the angular momentum quantum number (l) is 2, it corresponds to a d subshell for the principal quantum number (n) of 3 or greater values.

Find the value of ‘ml’ for one d-orbital

If l = 2, the magnetic quantum number (ml) has the five possible ways such as −2, −1, 0, +1 and +2 values.  It corresponds to five d-subshells.  

Count the electrons in one d-orbital.

(c)

Expert Solution
Check Mark

Answer to Problem 7.61QP

The total number of electrons which can occupy in one d-orbital is 10 (c). 

Explanation of Solution

There are five d-subshells in every d-orbitals.  In one subshell, there are two electrons are occupied.  In d-orbital, (5 × 2) = 10 electrons are occupied.  Therefore, the total number of electrons which can occupy in one d-orbital is 10.

(d)

Interpretation Introduction

Interpretation:

The total number of electrons which can occupy in s, p, d and f-orbitals should be identified using the concept of quantum numbers.

Concept Introduction

Quantum Numbers

Quantum numbers are explained for the distribution of electron density in an atom. They are derived from the mathematical solution of Schrodinger’s equation for the hydrogen atom.  The types of quantum numbers are the principal quantum number (n), the angular momentum quantum number (l), the magnetic quantum number (ml) and the electron spin quantum number (ms). Each atomic orbital in an atom is categorized by a unique set of the quantum numbers.

Principal Quantum Number (n)

The principal quantum number (n) assigns the size of the orbital and specifies the energy of an electron.  If the value of n is larger, then the average distance of an electron in the orbital from the nucleus will be greater.  Therefore the size of the orbital is large. The principal quantum numbers have the integral values of 1, 2, 3 and so forth and it corresponds to the quantum number in Bohr’s model of the hydrogen atom.  If all orbitals have the same value of ‘n’, they are said to be in the same shell (level).  The total number of orbitals for a given n value is n2.  As the value of ‘n’ increases, the energy of the electron also increases.

Angular Momentum Quantum Number (l)

The angular momentum quantum number (l) explains the shape of the atomic orbital.  The values of l are integers which depend on the value of the principal quantum number, n.  For a given value of n, the possible values of l range are from 0 to n − 1.  If n = 1, there is only one possible value of l (l=0).  If n = 2, there are two values of l: 0 and 1.  If n = 3, there are three values of l: 0, 1, and 2.  The value of l is selected by the letters s, p, d, and f.  If l = 0, we have an s orbital; if l = 1, we have a p orbital; if l = 2, we have a d orbital and finally if l = 3, we have a f orbital.  A collection of orbitals with the same value of n is called a shell.  One or more orbitals with the same n and l values are referred to a subshell (sublevel).  The value of l also has a slight effect on the energy of the subshell; the energy of the subshell increases with l (s < p < d < f).

Magnetic Quantum Number (ml)

The magnetic quantum number (ml) explains the orientation of the orbital in space.  The value of ml depends on the value of l in a subshell.  This number divides the subshell into individual orbitals which hold the electrons.  For a certain value of l, there are (2l + 1) integral values of ml which is explained as follows:

ml = ‒ l, ..., 0, ..., +l

If l = 0, there is only one possible value of ml: 0.

If l = 1, then there are three values of ml: −1, 0, and +1.

If l = 2, there are five values of ml, namely, −2, −1, 0, +1, and +2.

If l = 3, there are seven values of ml, namely, −3, −2, −1, 0, +1, +2, and +3, and so on.

The number of ml values indicates the number of orbitals in a subshell with a particular l value.  Therefore, each ml value refers to a different orbital.

Electron Spin Quantum Number (ms)

It specifies the orientation of the spin axis of an electron.  An electron can spin in only one of two directions.  There are two possible ways to represent ms values.  They are +½ and ‒½.  One electron spins in the clockwise direction.  Another electron spins in the anticlockwise direction.  But, no two electrons should have the same spin quantum number.

Pauli Exclusion Principle

No two electrons in an atom should have the four same quantum numbers.  Two electrons are occupied in an atomic orbital because there are two possible values of ms.  As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.  If two electrons have the same values of n, l and ml values, they should have different values of ms

To find: Count the total number of electrons which can occupy in one f-orbital

Find the value of ‘l’ for one f-orbital

If the angular momentum quantum number (l) is 3, it corresponds to a f subshell for the principal quantum number (n) of 4 or greater values.

Find the value of ‘ml’ for one f-orbital.

(d)

Expert Solution
Check Mark

Answer to Problem 7.61QP

The total number of electrons which can occupy in one f-orbital is 14 (d).

Explanation of Solution

If l = 3, the magnetic quantum number (ml) has the seven possible ways such as −3, −2, −1, 0, +1, +2 and +3 values.  It corresponds to seven f-subshells.  

Count the electrons in one f-orbital

There are seven f-subshells in every f-orbitals.  In one subshell, there are two electrons are occupied.  In f-orbital, (7 × 2) = 14 electrons are occupied.  Therefore, the total number of electrons which can occupy in one f-orbital is 14.

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Chapter 7 Solutions

General Chemistry

Ch. 7.5 - Prob. 1RCCh. 7.6 - Prob. 1RCCh. 7.7 - Prob. 1PECh. 7.7 - Prob. 2PECh. 7.7 - Prob. 1RCCh. 7.8 - Prob. 1PECh. 7.8 - Prob. 2PECh. 7.8 - Prob. 3PECh. 7.8 - Prob. 1RCCh. 7.9 - Prob. 1PECh. 7.9 - Prob. 1RCCh. 7 - Prob. 7.1QPCh. 7 - Prob. 7.2QPCh. 7 - Prob. 7.3QPCh. 7 - Prob. 7.4QPCh. 7 - Prob. 7.5QPCh. 7 - Prob. 7.6QPCh. 7 - Prob. 7.7QPCh. 7 - 7.8 (a) What is the frequency of tight having a...Ch. 7 - Prob. 7.9QPCh. 7 - Prob. 7.10QPCh. 7 - Prob. 7.11QPCh. 7 - 7.12 The SI unit of length is the meter, which...Ch. 7 - 7.13 What are photons? What role did Einstein's...Ch. 7 - Prob. 7.14QPCh. 7 - Prob. 7.15QPCh. 7 - Prob. 7.16QPCh. 7 - Prob. 7.17QPCh. 7 - Prob. 7.18QPCh. 7 - Prob. 7.19QPCh. 7 - Prob. 7.20QPCh. 7 - Prob. 7.21QPCh. 7 - Prob. 7.22QPCh. 7 - Prob. 7.23QPCh. 7 - Prob. 7.24QPCh. 7 - Prob. 7.25QPCh. 7 - Prob. 7.26QPCh. 7 - Prob. 7.27QPCh. 7 - Prob. 7.28QPCh. 7 - Prob. 7.29QPCh. 7 - Prob. 7.30QPCh. 7 - Prob. 7.31QPCh. 7 - Prob. 7.32QPCh. 7 - Prob. 7.33QPCh. 7 - Prob. 7.34QPCh. 7 - Prob. 7.35QPCh. 7 - Prob. 7.36QPCh. 7 - Prob. 7.37QPCh. 7 - Prob. 7.38QPCh. 7 - Prob. 7.39QPCh. 7 - Prob. 7.40QPCh. 7 - Prob. 7.41QPCh. 7 - 7.42 What is the de Broglie wavelength (in nm)...Ch. 7 - Prob. 7.43QPCh. 7 - Prob. 7.44QPCh. 7 - Prob. 7.45QPCh. 7 - Prob. 7.46QPCh. 7 - Prob. 7.47QPCh. 7 - Prob. 7.48QPCh. 7 - 7.49 Why is a boundary surface diagram useful in...Ch. 7 - Prob. 7.50QPCh. 7 - Prob. 7.51QPCh. 7 - Prob. 7.52QPCh. 7 - Prob. 7.53QPCh. 7 - Prob. 7.54QPCh. 7 - Prob. 7.55QPCh. 7 - Prob. 7.56QPCh. 7 - Prob. 7.57QPCh. 7 - 7.58 What is the difference between a 2px and a...Ch. 7 - Prob. 7.59QPCh. 7 - Prob. 7.60QPCh. 7 - Prob. 7.61QPCh. 7 - Prob. 7.62QPCh. 7 - Prob. 7.63QPCh. 7 - Prob. 7.64QPCh. 7 - 7.65 Make a chart of all allowable orbitals in the...Ch. 7 - 7.66 Why do the 3s, 3p, and 3d orbitals have the...Ch. 7 - Prob. 7.67QPCh. 7 - Prob. 7.68QPCh. 7 - Prob. 7.69QPCh. 7 - Prob. 7.70QPCh. 7 - Prob. 7.71QPCh. 7 - Prob. 7.72QPCh. 7 - Prob. 7.73QPCh. 7 - Prob. 7.74QPCh. 7 - Prob. 7.75QPCh. 7 - Prob. 7.76QPCh. 7 - Prob. 7.77QPCh. 7 - 7.78 Comment on the correctness of the following...Ch. 7 - Prob. 7.79QPCh. 7 - Prob. 7.80QPCh. 7 - Prob. 7.81QPCh. 7 - Prob. 7.82QPCh. 7 - Prob. 7.83QPCh. 7 - Prob. 7.84QPCh. 7 - Prob. 7.85QPCh. 7 - Prob. 7.86QPCh. 7 - Prob. 7.87QPCh. 7 - Prob. 7.88QPCh. 7 - Prob. 7.89QPCh. 7 - Prob. 7.90QPCh. 7 - Prob. 7.91QPCh. 7 - Prob. 7.92QPCh. 7 - Prob. 7.93QPCh. 7 - Prob. 7.94QPCh. 7 - 7.95 Identify the following individuals and their...Ch. 7 - Prob. 7.96QPCh. 7 - Prob. 7.97QPCh. 7 - Prob. 7.98QPCh. 7 - Prob. 7.99QPCh. 7 - 7.100 A laser is used in treating retina...Ch. 7 - 7.101 A 368-g sample of water absorbs infrared...Ch. 7 - Prob. 7.102QPCh. 7 - Prob. 7.103QPCh. 7 - Prob. 7.104QPCh. 7 - Prob. 7.105QPCh. 7 - Prob. 7.106QPCh. 7 - Prob. 7.107QPCh. 7 - Prob. 7.108QPCh. 7 - Prob. 7.109QPCh. 7 - Prob. 7.110QPCh. 7 - Prob. 7.111QPCh. 7 - 7.112 An atom moving at its root-mean-square speed...Ch. 7 - Prob. 7.113QPCh. 7 - Prob. 7.114QPCh. 7 - Prob. 7.115QPCh. 7 - Prob. 7.116QPCh. 7 - Prob. 7.117SPCh. 7 - Prob. 7.118SPCh. 7 - Prob. 7.119SPCh. 7 - Prob. 7.120SPCh. 7 - 7.121 According to Einstein’s special theory of...Ch. 7 - Prob. 7.122SPCh. 7 - Prob. 7.123SPCh. 7 - Prob. 7.124SPCh. 7 - Prob. 7.125SPCh. 7 - 7.126 The wave function for the 2s orbital in the...Ch. 7 - Prob. 7.127SPCh. 7 - Prob. 7.128SPCh. 7 - Prob. 7.129SP
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