Chapter 8, Problem 8.28QP

Write the ground-state electron configurations of the following ions, which play important roles in biochemical processes in our bodies: (a) Na⁺, (b) Mg²⁺, (c) Cl⁻, (d) K⁺, (e) Ca²⁺, (f) Fe²⁺, (g) Cu²⁺, (h) Zn²⁺.

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $N{a}^{+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $N{a}^{+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Na$ is 11 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^1$

For $N{a}^{+}$ , one electron is removed from the outermost subshell. Hence, the atomic number becomes 10

Therefore,

The electronic configuration of $N{a}^{+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $M{g}^{2+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $M{g}^{2+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Mg$ is 12 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^2$

For $M{g}^{2+}$, two electrons are removed from the outermost subshell. Hence, the atomic number becomes 10

Therefore,

The electronic configuration of $M{g}^{2+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $C{l}^{-}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $C{l}^{-}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Cl$ is 17 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{5}}$

For $C{l}^{-}$, one electron is added to the outermost subshell. Hence, the atomic number becomes 18

Therefore,

The electronic configuration of $C{l}^{-}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $K^{+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $K^{+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $K$ is 19 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{1}}$

For $K^{+}$, one electron is removed from the outermost subshell. Hence, the atomic number becomes 18

Therefore,

The electronic configuration of $K^{+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Interpretation Introduction

Interpretation: Ground–state electronic configuration of $C{a}^{2+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $C{a}^{2+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Ca$ is 20 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}$

For $C{a}^{2+}$, two electrons are removed from the outermost subshell. Hence, the atomic number becomes 18

Therefore,

The electronic configuration of $C{a}^{2+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^6$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $F{e}^{2+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $F{e}^{2+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^6$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Fe$ is 26 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^{6}4s^2$

For $F{e}^{2+}$, two electrons are removed from the outermost subshell. Hence, the atomic number becomes 24

Therefore,

The electronic configuration of $F{e}^{2+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^6$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $C{u}^{2+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $C{u}^{2+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^9$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Cu$ is 29 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^{10}4s^1$

For $C{u}^{2+}$, two electrons are removed from the outermost subshell. Hence, the atomic number becomes 27

Therefore,

The electronic configuration of $C{u}^{2+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^9$

Interpretation Introduction

Interpretation:

Ground–state electronic configuration of $Z{n}^{2+}$ has to be written.

Concept Introduction:

Electron configuration is the distribution of electrons in the atomic orbitals. It gives an idea about the shape and energy of electrons in an atom.

There are 3 rules to decide the electronic configuration of an atom. They are,

• Pauli Exclusion Principle: No two electrons should not have same four quantum numbers in an atoms that is, it no two electrons should have same principal quantum number (n), same orbital angular momentum quantum number (l), the same magnetic quantum number ${\text{(m}}_{\text{l}}\text{)}$ or same spin magnetic quantum numbers ${\text{(m}}_{\text{s}}\text{)}$
• Aufbau Principle: In an atom, electrons fill according to the increasing energy of the orbital.
• Hund's Rule: The orbital having maximum number of electrons with same spin in separate orbitals is the most stable arrangement in an orbital.

Cation is formed when one or more electrons gets removed from the outermost subshell of an atom.

Answer to Problem 8.28QP

The electronic configuration of $Z{n}^{2+}$ is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^{10}$

Explanation of Solution

The orbitals are filled according to Pauli Exclusion Principle, Aufbau Principle and Hund's Rule. The maximum number of electrons that can be accommodating in each orbital is 2.

Since the ns orbitals have lower energy comparing to the np orbitals and ns orbital is filled first. The ns orbitals have lower energy comparing to the (n-1)d orbitals and are filled first.

The atomic number of $Zn$ is 30 and the electronic configuration is ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^{10}4s^2$

For $Z{n}^{2+}$, two electrons are removed from the outermost subshell. Hence, the atomic number becomes 28

Therefore,

The electronic configuration of $Z{n}^{2+}$ is given as:

${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}3d^{10}$