Chapter 8, Problem 113A

(a)

Interpretation Introduction

Interpretation: To determine the valence electron in argon.

Concept introduction:

The electron configuration of an element defines how its electrons are arranged throughout its atomic orbitals. Standard notation is used to represent atomic electron configurations, placing all electron-containing atomic subshells in sequential order. The number of electrons held by the subshell is indicated by superscript.

Answer to Problem 113A

8

Explanation of Solution

The outermost electron is considered a valence electron. The electronic configuration of argon is as follows:

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

The outermost shell has 8 electrons.

Thus, valence electrons in argon are 8.

(b)

Interpretation Introduction

Interpretation: To determine valance electrons in aluminum.

Concept introduction:

The electron configuration of an element defines how its electrons are arranged throughout its atomic orbitals. Standard notation is used to represent atomic electron configurations, placing all electron-containing atomic subshells in sequential order. The number of electrons held by the subshell is indicated by superscript.

Answer to Problem 113A

3

Explanation of Solution

The outermost electron is considered a valence electron. The electronic configuration of argon is as follows:

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

The outermost shell has 3 electrons.

Thus, valence electrons in argon are 3.

(c)

Interpretation Introduction

Interpretation: To calculate valence electrons in selenium.

Concept introduction:

The electron configuration of an element defines how its electrons are arranged throughout its atomic orbitals. Standard notation is used to represent atomic electron configurations, placing all electron-containing atomic subshells in sequential order. The number of electrons held by the subshell is indicated by superscript.

Answer to Problem 113A

6

Explanation of Solution

The outermost electron is considered a valence electron. The electronic configuration of argon is as follows:

  $\text{Se}:\left[\text{Ar}\right]3d^{10}4s^{2}4p^4$

The outermost shell has 6 electrons.

Thus, valence electrons in argon are 6.

(d)

Interpretation Introduction

Interpretation: To calculate valence electrons in beryllium.

Concept introduction:

The electron configuration of an element defines how its electrons are arranged throughout its atomic orbitals. Standard notation is used to represent atomic electron configurations, placing all electron-containing atomic subshells in sequential order. The number of electrons held by the subshell is indicated by superscript.

Answer to Problem 113A

1

Explanation of Solution

The outermost electron is considered a valence electron. The electronic configuration of argon is as follows:

  $\text{Be}:1s^{2}2s^1$

The outermost shell has 1 electron.

Thus, valence electrons in argon are 1.