Chapter 2, Problem 2.84P

Interpretation Introduction

(a)

Interpretation:

The number of electrons present in the outer shell of Si should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Si is 4.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Si (14) is 1s² 2s² 2p⁶ 3s² 3p².

On the basis of above electronic configuration, the outermost shell or valence shell is 3s 3p which contains four electrons.

Thus, number of electrons in outermost shell of Si is 4.

Interpretation Introduction

(b)

Interpretation:

The number of electrons present in the outer shell of Br should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Br is 7.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Br (35) is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁵.

On the basis of above electronic configuration, the outermost shell or valence shell is 4s 4p which contains seven electrons.

Thus, number of electrons in outermost shell of Br is 7.

Interpretation Introduction

(c)

Interpretation:

The number of electrons present in the outer shell of p should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of p is 5.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of p (15) is 1s² 2s² 2p⁶ 3s² 3p³.

On the basis of above electronic configuration, the outermost shell or valence shell is 3s 3p which contains five electrons.

Thus, number of electrons in outermost shell of p is 5.

Interpretation Introduction

(d)

Interpretation:

The number of electrons present in the outer shell of K should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of K is 1.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of K (19) is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹.

On the basis of above electronic configuration, the outermost shell or valence shell is 4s which contains one electron.

Thus, number of electrons in outermost shell of K is 1.

Interpretation Introduction

(e)

Interpretation:

The number of electrons present in the outer shell of He should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of He is 2.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of He (2) is 1s².

On the basis of above electronic configuration, the outermost shell or valence shell is 1s which contains two electrons.

Thus, number of electrons in outermost shell of He is 2.

Interpretation Introduction

(f)

Interpretation:

The number of electrons present in the outer shell of Ca should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Ca is 2.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Ca (20) is 1s² 2s²  2p⁶  3s²  3p⁶  4s².

On the basis of above electronic configuration, the outermost shell or valence shell is 4s which contains two electrons.

Thus, number of electrons in outermost shell of Ca is 2.

Interpretation Introduction

(g)

Interpretation:

The number of electrons present in the outer shell of Kr should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Kr is 8.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Kr (36) is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶.

On the basis of above electronic configuration, the outermost shell or valence shell is 4s 4p which contains eight electrons.

Thus, number of electrons in outermost shell of Kr is 8.

Interpretation Introduction

(h)

Interpretation:

The number of electrons present in the outer shell of Pb should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Pb is 4.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Pb (82) is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p².

On the basis of above electronic configuration, the outermost shell or valence shell is 6s 6p which contains four electrons.

Thus, number of electrons in outermost shell of Pb is 4.

Interpretation Introduction

(i)

Interpretation:

The number of electrons present in the outer shell of Se should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of Se is 6.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of Se (34) is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁴.

On the basis of above electronic configuration, the outermost shell or valence shell is 4s 4p which contains six electrons.

Thus, number of electrons in outermost shell of Se is 6.

Interpretation Introduction

(j)

Interpretation:

The number of electrons present in the outer shell of O should be identified.

Concept Introduction:

The protons and neutrons of an atom are present in the nucleus of an atom whereas the electrons are always moving around the nucleus of an atom that is they possess kinetic energy. The lowest possible energy level of an electron in an atom is its ground state.

The electrons are arranged around the nucleus of an atom in an increasing order of energy levels and this description of orbitals of atom occupied by electrons is known as electronic configuration.

Answer to Problem 2.84P

The number of electrons in outermost shell of O is 6.

Explanation of Solution

Electrons are distributed in the orbitals of the subshell. The specific region of space in which the movement of electrons is confined is said to be shells which are divided into subshells and are s-, p-, d-, and f-. Among these subshells, the electrons are grouped as orbitals.

The number of electrons that these subshells can hold is:

s-block - 2.

p-block - 6.

d-block - 10.

f-block - 14.

The electronic configuration of O (8) is 1s² 2s² 2p⁴.

On the basis of above electronic configuration, the outermost shell or valence shell is 2s 2p which contains six electrons.

Thus, number of electrons in outermost shell of O is 6.