Chapter 11, Problem 71A

(a)

Interpretation Introduction

Interpretation:

The electronic configuration of ${\text{Sr}}^{2+}$ needs to be determined.

Concept Introduction:

An electronic configuration is the distribution of electrons in atomic or molecular orbitals of an atom or molecule or ion.

Answer to Problem 71A

The electronic configuration of ${\text{Sr}}^{2+}$ ion is $\text{[Kr] }$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{6}}$ .

Explanation of Solution

The atomic number of strontium is $38$ . So, the electronic configuration of strontium can be written as:

  ${\text{[Kr]5s}}^{\text{2}}$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{6}}{\text{5s}}^{\text{2}}$

Now, two electrons are removed from the strontium to make ${\text{Sr}}^{2+}$ . Hence, the electronic configuration becomes:

  $\text{[Kr] }$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{6}}$ .

(b)

Interpretation Introduction

Interpretation:

The electronic configuration of ${\text{S}}^{2-}$ needs to be written.

Concept Introduction:

An electronic configuration is the distribution of electrons in atomic or molecular orbitals of an atom or molecule or ion.

Answer to Problem 71A

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

Explanation of Solution

The atomic number of sulfur is $16$ . So, the electronic configuration of strontium can be written as:

  ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^4$

Now, two electrons are added in sulfur to make ${\text{S}}^{2-}$ . Hence, the electronic configuration becomes:

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

(c)

Interpretation Introduction

Interpretation:

The electronic configuration of ${\text{Ga}}^{3+}$ needs to be determined.

Concept Introduction:

An electronic configuration is the distribution of electrons in atomic or molecular orbitals of an atom or molecule or ion.

Answer to Problem 71A

The electronic configuration of ${\text{Ga}}^{3+}$ is ${\text{[Ar]3d}}^{10}$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{3d}}^{\text{10}}$ .

Explanation of Solution

The atomic number of Gallium is $31$ . So, the electronic configuration of Gallium can be written as:

  ${\text{[Ar]3d}}^{\text{10}}4{\text{s}}^2$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^{\text{2}}{\text{3d}}^{\text{10}}{\text{4p}}^{\text{1}}$

Now, three electrons are removed from Gallium to make ${\text{Ga}}^{3+}$ . Hence, the electronic configuration becomes:

  ${\text{[Ar]3d}}^{10}$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{3d}}^{\text{10}}$ .

(d)

Interpretation Introduction

Interpretation:

The electronic configuration of ${\text{Cu}}^{2+}$ needs to be determined.

Concept Introduction:

An electronic configuration is the distribution of electrons in atomic or molecular orbitals of an atom or molecule or ion.

Answer to Problem 71A

The electronic configuration of ${\text{Cu}}^{2+}$ is ${\text{[Ar]3d}}^9$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{3d}}^9$ .

Explanation of Solution

The atomic number of copper is $29$ . So, the electronic configuration of Copper can be written as:

  ${\text{[Ar]3d}}^{\text{10}}4{\text{s}}^1$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{4s}}^1{\text{3d}}^{\text{10}}$

Now, two electrons are removed from Copper to make ${\text{Cu}}^{2+}$ . Hence, the electronic configuration becomes:

  ${\text{[Ar]3d}}^9$ or ${\text{1s}}^{\text{2}}{\text{2s}}^{\text{2}}{\text{2p}}^{\text{6}}{\text{3s}}^{\text{2}}{\text{3p}}^{\text{6}}{\text{3d}}^9$ .