Chapter 8, Problem 8.21QP

Group the following electron configurations in pairs that would represent similar chemical properties of their atoms:

1. (a) 1s²2s²2p⁶3s²
2. (b) 1s²2s²2p³
3. (c) 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶
4. (d) 1s²2s²
5. (e) 1s²2s²2p⁶
6. (f) 1s²2s²2p⁶3s²3p³

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (a) with   ‘$1s^{2}2s^{2}2p^{6}3s^2$’ electron configuration

Answer to Problem 8.21QP

Pair 1: (a) $1s^{2}2s^{2}2p^{6}3s^2$ and (d) $1s^{2}2s^2$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (a) ‘$1s^{2}2s^{2}2p^{6}3s^2$’of an element has 2 valence electrons, so the element present in group 2A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (b) with ‘$1s^{2}2s^{2}2p^3$’electron configuration

Answer to Problem 8.21QP

Pair 3: (b) $1s^{2}2s^{2}2p^3$ and (f)$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (b) ‘$1s^{2}2s^{2}2p^3$’of an element has 5 valence electrons, so the element present in group 5A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (c) with ‘$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$’electron configuration

Answer to Problem 8.21QP

Pair 2: (c) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$ and (e) $1s^{2}2s^{2}2p^6$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (c) ‘$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$’of an element has 8 valence electrons and also it has the complete octet configuration. Octet rule refers the tendency of atoms to prefer eight electrons in the valence shell to form a stable configuration that leads to present the element in group 8A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (d) with   ‘$1s^{2}2s^2$’ electron configuration

Answer to Problem 8.21QP

Pair 1: (a) $1s^{2}2s^{2}2p^{6}3s^2$ and (d) $1s^{2}2s^2$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (d) ‘$1s^{2}2s^2$’of an element has 2 valence electrons, so the element present in group 2A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (e) with ‘$1s^{2}2s^{2}2p^6$’electron configuration

Answer to Problem 8.21QP

Pair 2: (c) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$ and (e) $1s^{2}2s^{2}2p^6$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (e) ‘$1s^{2}2s^{2}2p^6$’of an element has 8 valence electrons and also it has the complete octet configuration. Octet rule refers the tendency of atoms to prefer eight electrons in the valence shell to form a stable configuration that leads to present the element in group 8A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To Know the reactivity of an element (f) with ‘$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$’electron configuration

Answer to Problem 8.21QP

Pair 3: (b) $1s^{2}2s^{2}2p^3$ and (f)$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$

Explanation of Solution

Since only the valence electrons involve in bonding, electrons present in the outermost shell of an atom, response for the chemical properties of an element. The given electron configuration (f) ‘$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$’of an element has 5 valence electrons, so the element present in group 5A.

Interpretation Introduction

Interpretation: The given electronic configurations of the elements have to be grouped, that represent elements with similar properties

Concept Introduction: In the periodic table the elements are grouped based on their valence electrons, so all the elements within a certain group have similar properties. Since only the valence electrons involve in bonding, reactivity of an element depends on the number of electrons present in the valence shell of the atom.

To group the properties of the elements with given electron configuration

Answer to Problem 8.21QP

Pair 1: (a) $1s^{2}2s^{2}2p^{6}3s^2$ and (d) $1s^{2}2s^2$

Pair 2: (c) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$ and (e) $1s^{2}2s^{2}2p^6$

Pair 3: (b) $1s^{2}2s^{2}2p^3$ and (f)$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$

Explanation of Solution

Elements present in the same group have similar properties, based on this the given electron configuration of the elements is paired.

Pair 1: (a) $1s^{2}2s^{2}2p^{6}3s^2$ and (d) $1s^{2}2s^2$

Pair 2: (c) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^6$ and (e) $1s^{2}2s^{2}2p^6$

Pair 3: (b) $1s^{2}2s^{2}2p^3$ and (f)$1s^{2}2s^{2}2p^{6}3s^{2}3p^3$